X2. I never knew Grand Prixs were made with a manual.
Royal Pontiac did some special G/Ps with worked 428s and 4 speeds, their usual Bobcat stuff.
The Big Bird T-bird has the short rear deck, long hood proportions that are associated with muscle cars. Later Thunderbirds were too sedan like in shape. Put a blower and some Cragars on that large T-bird and it might make it. You can build a hot 460. Swap in an aluminum intake manifold. That will save you 100lbs for a start.:3gears: