Chuzz

Hey guys, newbie here. I did check in on the newbie forum. I've got a question about the 90 S-10 I just picked up for my son. First off, the horn doesn't work on it. I removed it and tested it with the battery and the horn is great!! Very loud. Checked the fuse box and the fuse was blown, put in a new one and it still doesn't work. Checked the fuse box for power and it has power going to the the box and there's power at the wire on the horn. I'm thinking maybe a bad relay?? Can anyone tell me where the horn relay is on this truck? I've been all under the hood and dash and can't find anything that even resembles one. The cigarette lighter is on the same circuit and doesn't work, but I discovered the wire to it had been cut by whoever put the crappy Jensen cd player/radio in. That will be replaced later. I also would like to know how reliable these 2.5 engines are. It only has 104,000 miles on it and when I started it this morning at 38 degrees, I noticed a lot of valve ticking. I'm hoping an oil change with some good oil will help this. Also, can anyone tell me if a later model GM cd player/ radio will fit and if so, which ones? I'd really like to find some bucket seats for it and build a console in the middle for storing cd's and the such. And ideas on what year buckets would be a direct fit? Sorry about so many questions, but as I said in my intro, been mainly a Mopar man for over 35 years, so am not familiar with the Chevy's at all. Thanks in advance.