Re: OMC stringer mount, no fwd??
You have a electric shift. Could be the spring in the lower. Got a manual your gonna need one for this fix.
I recommend the factory original manual and a guy on e-bay out of Long Island NY has them. Second best is seloc. If you get the seloc you need page 10-1.
There is a whole procedure for removing the lower however the whole drive does not have to be removed.
Maybe just maybe you have a bad connection for the wire. There are 2 coils in the lower maybe it's the coil.
Good luck !