Masthead revisited

[Sea Change]

There are epoxy methods that include graphite in the mix for bearings such as rudder stock heals. West System has a product.

423 Graphite Powder | WEST SYSTEM Epoxy

West also have instructions for Epoxy to aluminium bonding https://www.westsystem.com/app/uploads/2022/12/650-K-Aluminum-Kit-Instruction.pdf

If it was me, I would try and repair with epoxy, inspect later and then take it from there. Cutting out and welding in is a big deal, easy for a skilled worker, but at a higher risk to you for a person who thinks they are skilled and trashes your truck.

Just returning to this option, the slight problem is that inspection is very difficult.
With great care I have previously managed to remove the main and topping lift sheaves with the mast up. Because I didn't want anything to fall down inside the mast, it involved super glueing a cable tie to the sheave and then rotating it round slowly until I could complete the circle, and then had some way of tying a line on to the sheave. Fun and games while dangling in a harness.

With the sheaves removed, it's almost impossible to see inside the box. I'd be able to feel around for damage at best.

For the forward two sheaves, which are admittedly less of a concern, you can't access the pin/axle without removing the masthead box completely. So no inspection possible.