without the tilt quadrant, the motor should just be against the intermediate and with some force, someone should be able to lift the drive unless something else is binding.
could be the lower pins binding
could be the true-course parts are binding
could be the OP is underestimating the force...
no, your new transducer will have new wiring. simply pull out the old wiring with the old transducer and use that to pull a section of cord thru. then use the cord to pull the new transducer wiring thru.
3/4" BCX plywood, a tube of tite bond III, cut 2 pcs of wood to match transom, laminate together with the tite bond III, then paint the wood with the old timers wood formula (do a search on iboats) then install.
start with cleaning your battery cable connections. then the block end of the battery cables, and work your way up to the helm.
you most likely have bad connections, and probably at the ground block under the helm.
congrats on your new purchase. I still dont like the grill and headlights of the new hyundai myself. then again, there was a lowered 1962 suburban with two aluminum canoes on top at the camp ground that I just drooled over.
