What size 49 truck?

By "pulling truck" do you mean sled pulling at the county fair? Or a trailer on the road?

If it's a 1 ton or larger I say leave the frame it has under it and add 4wheel drive.
The bigger problem with a new or old frame may be finding a strong enough driven front axle that is narrow enough to fit without trimming the fenders or an extreme lift.

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-