If you have the rims powder coated, you have to be very careful (in my experience) about the powder buildup on the bead seating area. I'd actually request that the beads be left bare, or if anything very lightly coated. My powder guy laid a nice heavy silver on my 250SX rims and I have not been able to succesfully seat the beads on the two new OEM (i.e. priceless) tires I have for them. I'll be stripping the powder from the bead areas and trying again later, but be careful with powder.
With all that said, powder over spray paint any day. Spray paint will only look good once: right after you spray it. After that it is all downhill.
Also, pay attention to the lugnut style required for the wheels you get. I think the Big Red did the same as the SX: 85 used flat nuts, and 86 on used tapered seat (acorn) style lugnuts. Just be aware of this when you start mixing and matching wheels to make sure you are using the proper lugnuts for the wheel.
- Frank
1984 200ES Big Red
1985 350X (x2)
1986 350X
1986 250SX
1984 Auto-X
1984 ATC70
1985 ATC70