Electrical problem....HELP

[SWINGSAX68]

Running lamps (tail lamps, side markers, front markers) went out on me today , as well as the dome light and gauge cluster. . figures all run to the same fuse. I replaced the fuse with a AGC 20...bought it at the corner store needed a quick fix. Now running lights but no turn signals, switch out hazard light fuse with turn signal fuse...bingo, no prob. An hour later ready to leave my buddies place A.O.K......get to my street and I notice that my gauge cluster is out and sure enough, no running lamps and no brake lights...turn signals working a bit faster.....

I think I may have a short somewhere....maybe in my tail lamps....some wires are corroded off of the tail lamp plug...could that be it??? How about the brake light switch???? It is late and no light to check it out...gonna do it tommorrow. Could bad ground or lesser ground create a short???
Thanks!!!
-Roger...

P.S. drivers side tail lamp was a bit fussy about a week ago, had to jiggle wires to get it to work, but even then didn't work when brakes pressed. At that time passenger tail lamp was working. but after that all was fine until now......