Triumph Repair: Spitfire 1500 electrical, fuse block, heater blower

Question
I recently purchased a 1974 Spitfire and I'm having some minor electrical problems. The heater/blower and wipers only work "sometimes" - both work or neither will work. Tail lights and brake lights also work inconsistently. I've replaced all bulbs and sockets and have cleaned all connections, which has improved the problem but not eliminated it. Right now both brake lights work but the right is very dim while the left is very bright. I'm pretty capable with mechanical but know very little about electrical. Any help or pointers to troubleshoot is greatly appreciated

Answer
Hi John,
It sounds like a bad ground problem in the back but the other stuff, I would first remove the fuses and sand the fuses and sand the spring clips in the fuse block. They are noted for having intermittent bad connections.

If that don't solve the problems you need a wiring diagram and pick only one circuit at a time and start tracing with a test light (while it is in the failed mode)

If you don't have a diagram, let me know and I will put one up on my web site for you to copy.

Howard