I have recently bought a 4 speed auto '81 280 SL and now have it pretty well sorted. I would like to install a higher ratio diff. I believe the original ratio is 3 . 69. Ok for acceleration but revs too high at cruise on the motorway. There seems to be very very many ratios in the total Mercedes range but where can I find, say, a 3.27 and would it fit with no mods ? I did a similar diff swap on my MGA 1500 4.3 to 3.9 , engine pulls it well and now cruses in the 60/ 70 mph at less than 4000revs. all advice appreciated Sean