I have a 1978 70HP johnson. The tilt/trim is starting to act up and I had it checked out at a local boat shop and they told me that the motor needed to be replaced. Rather than pay them $400 to replace it, I thought I'd try it myself. One factor is that the 3 wire motor had been replaced by a 2 wire motor, and the motor is painted over with grey marine paint. Two questions...<br /><br />Is there a simple/logical way to determine the replacement motor? Looks like the 1981-1992 OMC three screw unit.<br /><br />Second, looks like I can't get to the inner screw on the motor without removing the outboard itself. Is there a trick? Anyone have any experience with this?<br /><br />Thanks<br /><br />Happy boating...