78 lwb to swb (tub dimensions)

[cardar911]

Hi guys I know covered 100 times..
Got a 78 c20 lwb converting to a c10 swb.. so its 14inches off the frame before the diff and 4-6 after..
Now the question is the swb tub..these are hard to get around here so im going to chop to size.. I need to know how much to cut out of the lwb to make it swb.. I guess the same 14inches like the frame before the diff but how much after the diff and any total measurements..
Thanks in advance guys

[Captkaos]

Cutting down the frame:
http://www.73-87chevytrucks.com/lwb_to_swb.htm

I recommend using a different method of cutting though.  I would mark the 14" area an notch it like this:

 
I would use this a a guide: http://forum.73-87chevytrucks.com/smforum/index.php?topic=7334.msg43642#msg43642

Cutting down the bed:
http://forum.73-87chevytrucks.com/smforum/index.php?topic=26656.0

[cardar911]

Very good write up indeed the motivation I need.. but the tub sizes arent detailed in these posts though

[SkinnyG]

14" is cut out behind the cab, so 14" will need to be cut out of the box between the front bulkhead and the fuel filler bump.  I cut 5" off the back of the frame as well.  Some cut 6".  My shortbox has 71" inside-to-inside of the stake pockets, so cut the difference out of the back. 

I intended to shorten the longbox off mine, but I lucked out and found a shortbox locally for less than the cost of the replacement wheel arches I would have needed.

[Captkaos]

The top link I posted describes the whole process with measurements.