So you have new one piece drop center rims for 20" bias ply tires? Will they require a tube?

I had not seen that kind of rim, but it looks like you have a good plan and it should work out assuming the back spacing works with the old center and where it can be placed in the new rim.

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-