1991 240dl wagon

Hey there everyone, I have two issues today. I had just replaced the tailgate wiring harness and while it worked fine right after i put it in some time over night something went wrong. I went to start it the next morning and no radio. I thought "fine, maybe it's a little hot out and my radio is not used to it", but after a while i checked and No.1 fuse is blown, I replace it and start the car and pop it goes. I did the stupid thing and tried the next fuse up (since the radio is upgraded) and it blew right when i started it. This problem happen to anyone else?

also, i checked the electrical line at my in tank pre-pump and no voltage was even getting to the pump. Which leads on the fuel pump relay should i check to see if that is the problem? (still waiting on my Bentley bible, have the haynes)