When I restored my 63 SWC my firewall and fuse connections had corrosion. I purchased some contact cleaner from Radio Shack and cleaned all terminals contacts with cleaner and a brush. I also used some electrical contact grease on all connections. I un-wrapped the harness inspected all wires and repaired the temperature-sending unit wire and re-wrapped the harness.
Thanks for your input. It looks like there are only 2 screws holding the fuse block to the inside of the firewall. It seems pretty straight forward to pull it free. Are there any tricks or trouble spots?
The two screws connect the fuse block from the inside firewall to the terminal connector on the engine bay side of the firewall. If I remember correctly the only problem I had was with firewall insulation. The biggest problem I see is working under the dash. It gets real tight under there. You will want to document the routing of all the wires prior to removal. I removed my dash to restore the birdcage and to install new dash pads.
Picture of the new pads and a newly vinyl covered center dash.