Topping lift
In order to use a topping lift and have it be adjustable, there must be at least one block or sheave at the masthead. On my Oday 272 there is a sheave (one of several) at the masthead. When I bought the boat, the topping lift was led down inside the mast, out through a sheave at the foot and secured on a cleat on the port side of the mast close to where the boom meets the spar. I have since lengthened and rereeved the line so that it leads back to the cabintop on the port side to a line clutch. This allows me to control the topping lift from the cockpit. I single-hand a great deal of the time and have moved most controls to the cabintop so that I don't have to go forward as much. If there is no sheave at the masthead, you will have to install a block on the aft side of the mast and lead the line through the block to a cleat on the mast or, as I did, back to a cabintop clutch. If you lead it back to a clutch on the cabintop, I would recommend a deck organizer with at least two, better three sheaves in it. This will allow you to lead some of the other lines back to the cabintop in the future. If the line must be led outside of the mast, make sure it is led so that it doesn't get tangled with any fittings or gear on the mast. You could use a couple of fairleads if need be.Not a difficult or expensive upgrade.Regards,Tom