New CD player, now blowing marker light fuse...any ideas?

[shiner2001]

I just changed CD players in my 90 Suburban today and after I did, I am blowing the fuse for my parking and tail lights when both they and the radio are turned on at the same time. I thought the 12v constant that I picked up behind the radio might be the culprit, so I changed power for my radio to a dedicated 12v constant on the fuse box (upper left corner), but the problem persists. After going through 3 fuses, I finally just took the radio out so I could get on with running my errands (which now included stopping to get more fuses). Once I got back home, I tried one more time, but this time (vehicle running), I turned on the radio and then the lights, but the fuse didn't blow. This time the radio just went off. I figure that might have something to do with my 12v switched power to the radio, so tomorrow I am going to pick that up from a different source (hopefully directly from the fuse block) and see if that solves the problem Does anyone else have any suggestions other than that as to what might be causing the problem or what a possible fix could be?

Thanks in advance!!