Put something on the gunnel that will be high enough when you put a bar across it that the motor will clear the floor.Almost like making a small A-frame in the boat.Something like a few 4x4s three-four feet long stacked on top of each other.Bar across it with a come-along/hoist attached to it.Pull it up and roll it forward or leave it in place and work on it like that,after bracing from underneath.... Or.... Not sure what kind of room you have on the sides but if you have it use a tow trucks boom to pull it,Thats how I got a couple out of boat I had on a high trailer,cash worked the best when negotiating a price with the operator beforehand and everything was ready for him when he showed up.