We'll try the 350 front first, I suspect it's the better choice for the truck. But if the 470 front fenders look and fit the existing axle and wheels better then it will make for a better looking truck. If not then to bad, it's to late to scrounge up a decent 470 frame and come up with a suitable axle...

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-