4 speed conversion. Help or hurt value of car?

A car in 1000 pieces should not be reflected in by how much it might be worth if you sell it! You have a long road ahead, just do what makes you happy and worry about the value later! I think you'll find that the difference in value between the 2 transmissions will be negated by your enjoyment of what you decide!! In the end, value doesn't matter as much as enjoyment!!