unless your 230 is pretty rough, you will destroy the value of it unless you do a very sanitary job.

some would ask why you need ac in a convertible.

but i would prob go with something very similar to the original but with ac capability. and then go with an ac setup as offered from benz in a sl chassis of the same type as you have.

probably most cost effective thing is to sell your car and buy one with air. but that wouldnt be as much fun.

good luck

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.