Trailer Wiring

I'm not sure if this is the correct forum or nor, but here it goes. With my 98 Dodge Ram Van 1500, I'm having trouble with my trailer wiring. I seem to have a short somewhere because the fuse in my engine compartment keeps blowing when I'm towing a trailer. It's done it on three different trailers, so i know it's not the trailer. I think the trouble is at the rear of the van where I did the splicing to add in two plugs when I got the van seven or eight years ago because I've moved the wiring around and I've stopped blowing fuses. I'm wondering if anyone knows of a wiring harness that makes it easy to have multiple plugs that would have it's own fuses or possibly resettable circuit breakers? I haven't found anything yet, and was wondering if I just wasn't looking in the right spot. any help would be great.

Thanks!