I will be posting my solution to replacing the original problematic switch on the older SB-1 without having to drill mounting holes for the switch and using the existing circuit board.... if anyone is interested.
I used the Megaswitch-P from StewMac.
On this guitar, the 5-way switch was part of the circuit board. I removed the switch mechanics and used an adhesive foam strip to attache the circuit board to the Megaswitch. The circuit board is the passive guitar circuit capacitors and resistors. It also has a fuse that attaches to the ground wire from the bridge... first time I have see that. You can see the fuse at the top of the board. Awesome protection from a deadly shock. Also the switch mounts to a metal plate that is glued to the body of the guitar. I had to cut down the screws to mount the switch from the inside. Otherwise, you have to drill two holes in the top of the guitar to mount the switch.