The Stovebolt Site Forums The Shop Area Driveline Question on switching to radials on my 1953 3100

I recently bought a '53 3100 pickup. The truck has old bias ply 650/16 tires. I want to switch to radial for better ride and handling, and also to reduce the height about 2 inches so I can get it into my garage. I would like to keep the 16" wheels. Any suggestions. Also it has the 216 engine. I replaced the carburetor, plugs, points, etc. and it runs better but still backfires through the carburetor at times. It has an exhaust leak around the head riser rod on the exhaust manifold. Any suggestions on what would be causing it to backfire? Thank you.