Backspacing of GM 16" and 16.5" 8 lug wheels

[AJMBLAZER]

Anyone know the backspacing of the following GM 8-lug factory wheels?:


1. 16.5" steel wheels from back in da day

2. 16" steel wheels from the 80's before IFS ruled the day

3. 16" steel wheels from 88-99 IFS 8 lug trucks

4. 16" steel wheels off of 99+ 2500 and 2500HD trucks

5. 16" aluminum wheels off of 99+ 2500 and 2500HD trucks

I've got a set of the first ones on my truck and rough measuring says they are about 5". That kinda surprised me.

Looking for something about 16x7 with 4-5" of backspacing.

 

[AJMBLAZER]

 

[BARRAZA]

80's cucv stock wheels were 16x6.5 with 4.5 inches backspacing

 

[AJMBLAZER]

Thanks man!
There's number 2.

Anybody else?

 

[AJMBLAZER]

I'm told Number 3, the 90's IFS trucks, were 16x7ish (7.5?) with 4.75" backspacing. Would explain why they stuck out more than the half ton IFS trucks' wheels.