I installed a permanent mast carrier aft, similar to boom gallows. The supports were made from old 6061 aluminum spreaders and the crosspiece is an old boom gallows board from another boat. The support brackets were made from 1/4 inch plate aluminum using hand tools, drilled for a single u-bolt and a single through bolt on each side (1/4-20). The gallows board is held to the supports by u and through bolts as well. The board also will provide a place to hang dock lines not in use, and small fenders.