I have a 1980 380 SL Euro.I know there are a lot of real smart techs here,so here goes...Is there a model ID number stamped on the transmission.? If so Where is it.? I just did some extewnsive fuel work on it,and when I took it out for a ride,at about 20mph there is a loud knocking sound coming from the transmission,or torque converter??.It was sitting for about three years,but had no trouble before it sat.It has a 6 bolt transmission pan..The fluid in the transmission was very clean,and the filter was clean also.Any help would be greatly appreciated..Thanks...