1991 1/2ton 4x4 suburban wheel studs

[83 NM K10]

hey guys, i've been lurking around here for a little while reading & learning but came across an interesting deal today!

i have an 83 k10 i'm putting together but came across a 91 suburban that i couldn't pass up. 
anyway, i was rotating the tires this morning and found that the rear axle has 7/16" wheel studs and the front axle has 1/2" wheel studs.  both axles are 6 lug and all the wheels fit the 7/16" just fine...

thoughts, suggestions??!!

[fitz]

I can't help you with the wheel studs but I'd love to hear / see more details about the roof on that suburban.
That's a sharp rig, never seen one with a roof like that before.

[zieg85]

I did a little cross checking and what I have found is they had 7/16" in 1991.  Front rotors must have been changed is what I am thinking