electric speedo into a car with a mechanical one
 

A friend is doing a transmission swap. The donor car (W126 300se) had an electrical speedometer and the receiving car (W124 300E) has mechanically driven speedo.

What's the "best" way to do the swap? (other than find a different donor).

Thx -CTH

If the swap was going the OTHER way.. mechanical into electronic, no problem.

BUT the installing the 300SE trans into the 300E means the speedo will be inop!

IF you try installing all of the mechanical speedo drive gears into the other trans, they will burn out. There isn't any provision to lubricate that set of gears on the electronic speedo trans