I have a 1968 85 HP Evinrude that has a bad lower unit. It is a manual shift unit. I am trying to determine what options I have for finding a replacement lower unit. Can the electric shift lower unit be used with my motor if I run the wires through the upper housing somewhere and up to the controls? Also, what other years and horse power's will work with my system? My model # is: 85853A, and serial is: E02053. Thank you for all your help.<br />Eldon