And now for something completely different...
I have stock 4.10 third members and a spare axle from an 85 4cyl 4WD toy. My son is building a street rod and would like to use my "free" rear axle. Can anyone guide me as to what if any 2 pinion 2WD third members will fit? I'm looking for a ratio between 3.2 to 3.55.

let me get this straight, your son is building a street rod and wants to use your 4x4 axle? remember,it's 6 lug. if you want a 5 lug 8" you need to find an earlier 2wd('69-78) as most if not all of them had the 5 lug 8", most 2wds got the 7.5 starting in the early 80s. however, just about every 2wd 4 speed or 1 ton rated truck came with the 8" too.

to answer your question about gears, i know the 8" came in 3.08 in some 2wd 4 speeds and also in 3.90. i DO know that 7.5s in 2wds were available with 3.42, 3.54 and 3.73 ratios, but i'm not entirely sure if you can get the 8" in a 3.54 ratio in the US(i've heard australia has them though)

all 8" diffs are interchangeable from '69-current. the only vehicles i know of that still have the 8" are 4runners, the last of them in trucks were used in '95

E-lockers used in Tacomas are 8". <img src="/forums/images/graemlins/smile.gif" alt="" />

Kyle-22r covered most of it.
The only thing I would add is that there were a few single wheel 2wd rear axles with the 4.10 and 4.30 ratios.
Hard to find though.
Most were dual rear wheels (think u-haul) and 6-lug, 4.10 and 4.30 ratios.
Hope this helps,
Todd

they're not hard to find! most if not all early-late 70s 2wds had a 5 lug, 8" rear end with 4.10 or 4.38 gears.

most 4 speed 2wds after that seemed to have a 3.08 8" rear end with 5 lugs as well

Thanks to all. Yeah, I was expecting to redrill the drums, etc. I was thinking this route because I was expecting to pay big bucks for a MOPAR or GM rear. NOT! I've found one from a Nova, non-posi 3.08, 8" 10 bolt for cheap.