should i replace my wiring harness?

[roberteberts]

Hi all,

I'm attempting to restore my 71 blazer and most of the electrical works OK besides a few issues but it's just a huge rat's nest under the dash and under the hood and alot of the wires look old and brittle not to mention over the years things were obviously modified, like different guages and extra componets & switches, so my question is should try to fix whatever needs fixing the best i can with what i have or should i get all new harnesses and install them? the thing is i'm really not very good with electrical, is there any really good wiring diagrams or manuals out there that would help alot or would i just be better off taking it to someone who knows what thier doing and having them do it, keeping in mind i don't have alot of money right now to pay someone.