You might want to keep the battery...
Seriously, rip it all out unless except for accessory wiring. If the old wiring harness is decent maybe somebody here could use it. I made new fuse blocks for power and ground, much simpler and "easier" for me, should be a piece of cake for you. I kept the mounting hardware for the miscellaneous stuff, was useful to hang new relays, etc from. Good Luck and take lots of pics for us.....
