I agree with using the 3 piece wheels. I restored all 6 of mine last winter. I had 3 two piece wheels and 3 three piece wheels. I had one of the 2 piece wheels come apart after hitting a very small pot hole. I was able to purchase some wheels from a couple members on the SB and now I just need to install the other two, but they are on the inside rear and I haven't had a reason to pull them off.
Keep the old wheels. These trucks look to funny with the shorter tires.