I seriously doubt a valve body change would work, the old PB 727's had rear pumps the new ones don't. The problem is how it's shifted.

Best I can think of is using a floor shift from an early MoPar, such as my 65 Cuda, and modifying the action to be more race oriented.

They say there are no such thing as a stupid question.
They say there is always the exception that proves the rule.
Don't be the exception.