On my way back home from driving my wife to work I was pulled over by a friendly police man to inform me that my brake lights were out. More specifically that my center light worked but the lower ones did not. I was a tad perplexed by this since I had just replaced the brake light switch not a week or two before. I drove back to my apartment and in the parking lot fiddled with wiring for about an hour or 2.

Odd thing I found- The brown wire which according to my diagram goes straight from rear right brake light to the bulb failure was cut and spliced to the red wire on the rear left brake light. I imagine the idea of whoever did that was the signal would go from the red, through the spade connector and on to the right brake light. I undid this and reconnected the brown wire with the cut brown wire. This however did not solve the issue. At least it didn't make it worse.

After swapping the bulb failure relay and checking the fuse the issue persisted. I then crammed myself under the dash and fiddled with the brake light switch, after this my brake lights started to function again, however they never really worked right and still do not.

When tail lights are off (headlight switch turned all the way off) I get left brake, center brake light, and then right tail light filiment on the right brake light. It's noticably more dim.

When tail lights are on (headlight switch at parking lamp, or full on position) I get left brake light, center brake light, and a dark right brake light. Both tail lights function normally when brake pedal not depressed.

I have changed bulbs with no effect. Could there be an issue with the new brake light switch? Did I not put the connectors on the switch in the right place? Does this indicated some issue between the switch and the bulb failure relay?
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1990 245 DL in Denver, CO