So as the title says, halfway from driving back from the store yesterday my 1982 200T wagon had a pretty substantial electrical failure. - All turn signals - All parking lights - Both brake lights - Fuel gauge(not sure about the low fuel light) - Turn signal lights on the dash - Engine temperature gauge They all died on me. I managed to fix the brake lights by replacing the fuse which was pretty bent out of shape. I managed to get the warning light and indicator relay from under the shifter panel, I have a multimeter but I'm more of a mechanical side of things guy and im not too competent with car electrics, so if anyone knows how to test the relay I'd love to know. I also haven't figured out why my dash is all screwed up now too. I've been trying to find a common fault by looking at the cars wiring diagram but I haven't found the "magic bullet" of a common issue yet. My personal theory is that because they all went out while I was going in traffic down hill and using the brakes a lot, that there was some problem with the brake light fuse which didn't blow when it should've which then ended up somehow screwing up everything else. I'm mainly just concerned that after I fix and replace everything this will happen again and I have no idea what the root cause could've been. Anything that anyone could help me with would be greatly appreciated. Thank you in advance.

TLDR - all the things listed above went out simultaneously yesterday, if anyone has experienced something similar or has any idea what it could've been I would be very thankful for your knowledge!