I am going to be doing the same thing with my 3600. I am swapping in a 1/2 ton front axle so that I can convert to a 5 lug disc using this kit:
Basic 5 lug disc conversion kit I'm curious to see if the wheel mounting surface location changes much with this conversion.
I'm also looking for a steel wheel that will accept my original hub caps, preferably a 16 or 17 inch. I see plenty of 15 inch rims out there that will do the job though....
Hopefully a 7 inch in front, and 9 inch in back, if I can get wheels with the right back spacing. My rear axle will be 1/4 inch wider than stock on each side.
Truck nut- what brand and model of 8 inch wheels did you try to bolt up?