Hi Skip, I converted my M15 from the fixed motor mount to a lift mount as well. Because of the access problem; ....and I wanted to add a backing plate for the lift mount - my solution to gain sufficient access was to cut a rectangular opening in the aft Port cockpit seat surface. This gave me all the access I needed for easy working, and installation of the new lift mount, and when finished I installed a previously purchased rectangular hatch. The model hatch I used was: BOATER'S WORLD, 2006 Catalog; Page 414 - and I think it was, H Marine Stock No. 2-929-0050. The outside dimensions were 10 3/4" X 15" and it just fit into the area between the sail locker lid and the aft end of the cockpit. It has an O Ring seal and the lid locks in a closed position with a 90 degree turn of the D ring handle. I found that the big advantage of using the locking hatch was that it gave you excellent access for the dark back corner of the sail locker. I kept my cleaning bucket and materials there. Another opinion for your consideration. Connie ex M15 - LEPPO