If you use wide ratchet straps and put a twist in each side they don’t hum and flog at speed. I don’t know where I picked that up but it works!
For mast support I use a spacer block in the “hole” below the mainsheet track and screw the lighting board on a plank of wood to the outside. Another plank that sits edgeways on the aft tank is bolted through the lot so it is all clamped to the transom. 2 x 6″ coach bolts + wing nuts. The inner plank is shaped to take mast one side, boom the other. Rock solid, 30 mins to make, cost pennies. all weight spread over aft tank
If you replace wheel bearings keep old ones as spares with car spare tyre
Robert