Drill and tap
I recently installed a version of Lazy jacks on my 37, and the directions said to use a drill and tap, and provided both in the proper size in the kit. A nice touch.Also was my first trip up the mast in a bosun's chair.An experienced friend helped me and we marked the spots (on boom and mast) with a pencil, used a pointed punch to start an indentation to prevent the drill bit from slipping, and then drilled slowly (using lubricating oil), Avoid putting lots of pressure so you don't punch through and damage internal wires or lines. The tap the holes.I used two drills to mak the job go faster: one for the drill bit, and one for the tap.When the holes were ready I put silicone over the top of the holes and on the machine bolts to create a waterproof seal, and tightened by hand.Looks good and feels secure...Sanders