RALLYE wheel fitment questions

[stich626]

Hello..
my 71 c-10 long box.. that I thought I had a few sets of wheels to choose from are the wrong lug size, anyways..
wheel vintiques offers a "style 37 series" basicly a corvette rallye with the truck 5 on 5 bolt patten
I'm tore on either all 8" wide or 8" front and 10" rears..
the truck is only lowered in the back 2" to take the rake out of it..
as far as I can tell there isn't nything but worn 40+ year old springs that is off from factory ride height.
the 8" wide come with either 4" or 5" backspacing
the 10" wide it's either 4.5" or 5" backspacing.
thats the choices..
the truck has 7" fronts and 10" rears on it now..
but are alum centers with steel rim..
will that thick alum mounting flange skew my measurements if I measure the backspacing on the wheels on it now..

any help wood be great..

the wide rears look nice on it.. but.. how do these trucks wear the front tires.. ? will the fact of different sided tires and not being able to rotate them , really short'n there life.. more than say a newer car(my daily went 60k without rotate'n the tires,, I know)
if I go all 8" the rotation won't be an issue..

again thanks..

they also offer a style 66 rallye that is just a vette rallye but in 16" and 17" sizes
I'd also like any info on what sized tires look "right" in those sizes..

I'd think the 16 or 17 would help handle'n some..
input??