You could cut and strip the wires going to motor. Rig a jumper wire from battery to one wire and get motor in position to work on lift motor. On those 2 wires one is up and one is down so touching with a hot should tell you which is which. Once you have motor tilted up you can see how much room you have to work with. I would try to strip that sheath back, strip both wires back, slide on some heat shrink, solder wires together, heat shrink over connections then coat with liquid tape and wrap with electrical tape. Then figure out how to prevent it from happening again.