I,ve run my fuel line along the bottom of the tranny tunnel, brake line along the top & electrickery
at the top on the opposite side to the brake line,
basically put as much space between the fuel & electrics as possible, taking into account as "Tex " has mentioned on moving parts & the route past the diff.
Also, my electrics are totally enclosed in convoluted (sp) tubing thru the tranny tunnel area from the fuse box to the rear of the car then spurred off to each side for rear lights etc.
Don,t forget to ensure you use the correct spacing for attaching the various pipes & electrics when attaching to the chassis, IVA man will check that (I believe its 100mm maximum between the "P" clips within the tranny tunnel).
Hope this helps.
cheers
andy