Easy way
I did it in my Monsum 674I cuted the cover of the chain locker in two pieces.Under the middle part of the front (looking to the bow), I puted a piece of inox (5 mm.) with the exact holes for the chain, screws for the engine, etc. This piece of inox it is attached to the border of the locker with screws (every 15cm) all over the section sealed with sikaflex. I did a hole in the recuted original cover of fiberglass to pass the head of the windlass.The order part of the cover can be open when you want. In that way you can remove the chain when it's holding up.The box of electrical conections (Diods) is installed inside the boat, in the front of the cabin. I did a hole in the front panel to pass the electrial cables to the engine of the windlass and to the manual comander.Then I passed the electrical cables (two big ones) by the tube who is inside the bilge. In the front cabin these cables goes under the starbord "bed" next to the water deposit. And in the stern the cables goes next to the engine conected to the fuse (75 amp)and to the engine batterie.It seems complicated but with a pictures you are going to undertand the process.The most expensive part was the piece of inox (150 Euros), the "fat" electrical cables (red and black)(I dont remeber the price but near 100 Euros) and the electrical commander for the windlass (75 Euros).Please tell me if you need the pictures.Good LuckBest regardsToni Fuster