Kind of depends on which wiring harness you're using. An original type is pretty much self-explanatory in which case you probably wouldn't have asked. So I'll hazard a guess that you're going to use something with a fuse block like the Speedway 12 circuit deal. I put the fuse block for one of those centered with the bottom corners just touching the X stamped into the firewall on the drivers side. That puts it high enough to be out of sight and low enough to reach the fuses.

Steve


Steve


1946 1/2 ton