Electrical heck

[Pijuan]

My boggle began with my 1969 MGB running roughly, I then resolved my engine rough ride, then I noticed my brake light wern't working. I then began experiencing a series of issues that seem to take turns, first the brakes, then the gauges, the signals, and the headlights. They all seem to take turns handing off their dysfunction. I am not well versed in electronics so I am curious, does the ignition switch act as a switchboard to these other systems? If so, why is it near impossible finding a switch for 1969? I can find it up to m1968 and then it jumps to 1970. Anything?

 

[DNK]

He is a schematic for it
MGB Schematic

 

[DrEntropy]

First order of business is to physically check all the grounding points. Black wires. Disconnect and clean all of them. dielectric grease or some petroleum jelly will help keep them from corroding as quickly. A ScotchBrite pad is great for cleaning the various bullet connectors and such. A .22 cal. bore cleaning brush is good for the Lucar connectors' junction blocks.

The lights are not dependent on the iggy switch.

 

[fogliner]

X 2 on Doc's post!

Make the bullets look like this. I got a supply of female connectors and went through everything I could see and either replaced the entire connector after buffing the bullets and dabbing on some grease and just reconnecting them or brushing the inner pieces and re using them if they looked ok.
There are singles , doubles and triples as pictured.
This will do a lot to solve your problems. Some of the good(original) connectors have a copper or brass inner piece,I think the new ones are just tin though.
Let us know how it goes for you.

Mark