Author Topic: definitive dimensions/position for cutting the bed from a longbed to a shortbed  (Read 17454 times)

Offline moregrip

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First, there doesn't seem to be nearly as much information on cutting down the bed on a squarebody compared to the 67-72 crowd.

With that said, I'm seeing more and more examples of it lately, mostly on Instagram. It's pretty easy to see where the cuts are made but I'd feel a whole lot better knowing a few more details.

Like how much to cut out of the front and how much to cut out of the rear.

help!

I want to try this! I have a near perfect longbed to play with!

Offline SkinnyG

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14" behind the cab.   Pick a spot that makes it easy to do a fish plate when you're putting it together.

5" or 6" off the back.  It doesn't really matter.

My writeup:  http://www.gwellwood.com/project-cars/the-crusty-chevy/shortboxing-the-frame/
The Crusty Chevy: 1977 Silverado, shortboxed & dropped, potato-potato.

Offline SkinnyG

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Oh wait, the BED?

Prolly still 14" behind the cab, but cut it as close to the front of the box as you can, so you're not slicing in the middle of the panel.

I have a proper shortbed bed (not cut down), and the bed stake-pocket metal is 71" inside-to-inside measured in the bed.

I have stake-pocket hold-downs in the holes, so I can't get an accurate measurement - probably ~around~ 73-1/4" center-to-center)
The Crusty Chevy: 1977 Silverado, shortboxed & dropped, potato-potato.

Offline moregrip

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Exactly, the bed. I feel pretty dailed in with specs and procedure for cutting the frame and associated mods but there seems to be far less detail on cutting the bed down. that inner stake-pocket edge to inner stake-pocket edge measurement helps though. Is that exact?
« Last Edit: July 11, 2017, 07:22:57 AM by moregrip »

Offline Jason S

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Don't know if it shows what you're wanting, but have you looked through the thread linked below?

"Cutting down a Long bed to short bed dimensions"

http://forum.73-87chevytrucks.com/smforum/index.php?topic=26656.msg140416#msg140416
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1974 Chevrolet K10, Custom Deluxe, 350, SM465, NP203, 3.73's

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Offline VileZambonie

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It's not a popular modification as it usually ends up costing more $ and time. You can sell the long bed and put the $ towards finding a short bed or buying the parts to build one. Good luck whatever you decide to do.
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Offline AZ4X4SQBDY

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14" behind the cab.   Pick a spot that makes it easy to do a fish plate when you're putting it together.

5" or 6" off the back.  It doesn't really matter.

My writeup:  http://www.gwellwood.com/project-cars/the-crusty-chevy/shortboxing-the-frame/

Nice write up and web site.  8)

I just bought a wrecked 87 short bed off of a local member here and I'm debating on "how to" or "if I should" fix it. Clipping a front frame section from my long bed parts truck to my short bed rear frame is now an option. I had been looking for a complete frame.
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Offline harcorshe

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What about the bolt holes for the rear bumper? The picture looks like they would be blocked by the spring hanger...
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Offline SkinnyG

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My truck has the longer, heavy leaf pack, so the rear hangar is pretty far back on the frame.

I also fabricated my own rear-bumper-hangar/hidden-hitch that utilizes the holes I ~could~ get to.
The Crusty Chevy: 1977 Silverado, shortboxed & dropped, potato-potato.

Offline moregrip

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I asked a guy who has done a few of these what he takes out of the bedsides on the squarebody and its 14" in the front and 6" in the back, cuts look to be close to the outer edges of the bedsides.

Offline Captkaos

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This is on our main page under tech:
http://www.73-87chevytrucks.com/lwb_to_swb.htm

Offline moregrip

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This is on our main page under tech:
http://www.73-87chevytrucks.com/lwb_to_swb.htm

Thanks bro, I've read that tutorial SEVERAL times and others! I didn't catch the detail of cutting the bed down but I'll check again. For the frame I'll be using "Built by Brooks" bolt in brackets to secure the shortened bed frame:

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Offline moregrip

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general info/update:

I was able to confirm that the correct measurements for shortening the truck bed are in fact to remove 14" in front of the wheel-well and then to take 6" away from behind the wheel-well. There is a guy that has done a few of these on Instagram and I got actual dimensions published from the GM Heritage website.

Short bed stake-pocket (center to center) measurement is 73.4"
Long bed stake-pocket (center to center) measurement is 93.3"

So doing simple math 93.3" - 73.4" = 19.9" or roughly the 20" that needs to be taken out of the bed in the correct proportions of course.

Additionally, it was recommended to me that the cuts should be closer to the outer edges for aesthetics.

Here are some examples from a guy on Instagram (c10acres). I don't know him but his work is beautiful:



« Last Edit: July 22, 2017, 12:13:29 PM by moregrip »

Offline Captkaos

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Offline moregrip

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thanks Chris! Yessir, that was the first thread I saw that even but this evil idea in my head! Luckily I have a practice bed to work on first to test my ability to get this right before I go cutting a very nice longbed bed up!