I did that on a previously owned 245. I mounted the windless on the chain locker cover. The cover itself was not heavy enough so I cut a piece of 3/4 marine plywood and glued to the inter side of the cover. The I devised a lock system so that once the cover was closed it would be secure enough to withstand the pull of the windlass. The pull is horizontal rather than up so take that into consideration. You will need to run power line direct from the battery to assure you have adequate power. Check you windless install manual for wire size based on length. I used #6 cable.
