Welcome to CHR Adam. Numerous companies make IFS conversions for the '46, as well as upgrades for the rear to get some more modern components that will hold up to an engine with some horsepower and give you some much improved braking and handling, too....really comes down to how much you want to spend on the upgrades.

As Don mentioned, Speedway Motors offers the engine mount conversion kits. While you're at it, don't forget to upgrade (as in replace) the electrical system, really ads to the reliability issues of a good build!