8 Lug K20 Rim/Tire Question

[thump426er]

I've doen some searching on here to try and find a thread specifically on this and haven't been too successful.

I have a 72 K20 with the original 16 wheels with tires which measure out at 30.5" diameter. What I'd like to do is find some nice 8 spoke (or some style I like) rims to throw on it with a little bigger diameter tire. Hoping to get 32-33" in there. Looking at 17-18" rim diameter as well.

A few questions I have:
- what are my options in terms of searching for rims, eg: when I talk to tire rack or discount tire etc their computer doesn't show rims for those so they can't help out at all but I would guess that say an 85 3/4 8 lug would fit mine as well, I see on here that older ford 8 lugs fit??? What are some examples of other model year vehicles with rims that will and won't fit.

- How much back spacing would I need?

- What size tire can I get away with without rubbing on a stock ride height 72 K20.

Thanks for any input to this.