It's a roller reefing boom. Don't even try to use the roller reefing unless your sail hasn't been converted to slab reefing and there are no blocks etc. for the reefing on the boom. If that's the case, have reefing patches and cringles added to the sail and install cheek blocks to set it up for slab reefing.
The tang that the topping lift is attached to probably should be on the outboard
side, installed after the tang for the mainsheet which should be in inboard and installed first. Hopefully that will allow the topping lift tang to stand far enough outboard
to clear the hardware
on the end of the boom. Then the boom would be free to assume it's proper position with the sail track vertical. If changing the order of the tangs doesn't clear the tang away from the boom hardware
, you'll have to pull it off and straighten the tang and/or add spacers. Add more spacers, additional washers, so it stands farther away from the boom end till it clears the boom.
Roller reefing is a horrible reefing system that had no reason for being invented. Don't know why practically every boat, up until the very early '70s, came with it. Happiest day of my life was converting the main to slab reefing on my first boat. Of course, by then, the roller reefing had stretched out the leach and effectively ruined the brand new main in only a couple of reefing sessions.