Any suggestions on how to clean the plugs on the electrical system. I’m talking about the male and female connections. Is contact spay good enough or maybe something a bit more acid? Thank you

 

If badly corrode/dull I used fine wire wool with contact spray , then finished of with a toothbrush and the spray. The female halves can be quite hard to get clean, so a tiny file down them if they did not look very bright after the toothbrush treatment. Fine emery paper is good too, and can be rolled into a tiny tube for the female connections.
What I can say is that all the effort is really well worth it. After my redoing all the dash, console and engine bay and bulkhead connectors I could find, everything works more "confidently" and snappily, somehow. The earth connections wherever they may be are also extremely important to clean and protect with grease.

 

What 'Greg' said

 

I typically use 320-400 grit sandpaper that I have laying around. You can get files specifically for connectors to clean out female ends and its really great. Also very small brass or steel brushes like the nylon ones you can get for carb cleaning.