You're right about it being a neutral balanced unit.
What are your overall goals with the car? Are you trying to squeeze every last bit of E.T. out of it f or racing, or are you using it more for street/strip and just messing around?
If it's the latter, then the PTC unit that you're considering will be fine when you swap out to the Magnum motor. Otherwise, I agree with AbodyJoe. Hold off until you have the engine where you want it.
