Hi,
I'm from Germany and have replaced the original 4-speed gearbox in my 280SL against this 6-speed GETRAG (taken from the actual BMW 1 series) gearbox early last year. My rear axle transmission ratio is 3.92.
I couldn't have done any better! Have run the car for about 9,000 km since then. The new engine speed has lowered significantly and it is pure fun cruising with that combination.
Wouldn't hesitate to try it if I were you. Gearbox modification set cost around 6,500 EUR last year and contains everything necessary for the modification.
I've kept the original gearbox though in order to be able to strip down again if necessary.
Bye,
Wolfgang
