Myself, I would go with the 240 chassis since it has the totally bulletproof manual ac system. The work invovled is a little more since you will need to change the rear end as well and the speedo, the exhaust system and the radiator.

I would expect to pay my indie about 700 to put the stick tranny into the 300d including changing the drive shaft length.

I would expect to pay from 1000 to 1200 to put the 300 motor into the 240 chassis.

I have had both jobs done within the last for our five years. Both cars are working out well for us.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.