Jump on it. 4 speed trannys command a high price and might be worth close to $500 alone. That was a performance option. Even just the 3-pedal assembly is valuable. It is possible the engine is the more desired HiPo or "Commando" version with high compression pistons. If so, it would have had a factory 4 bbl iron manifold w/ Carter carb and finned valve covers. It might also even have the special exhaust with rear square resonator (still 1 exit tube). That would be the coolest 4 dr around and a neat sleeper.