I guess I thought the cost of the TT was one of the big attractions?

Otherwise, just run the 426 motor on the long course with a low pitched prop to keep the speed down (10x6 maybe).... Or a simple thing like a detuned muffler for 424.

Still going to be close to $250 at the end of the day, and if you want a carb vs. Venturi, another $35, etc..