Wiring nightmare

I'm building another Camaro, and the wires must have been installed by a spastic chimpanzee on meth. It's an ex-racer. In wiring the instrument lights, doesn't the fuel level sender (brown) tap in? I've made a custom instrument panel, but want to TRY to use as much of the original harness as possible. Any help would be appreciated.
Any experience with mild, Pre-roller type cams? My bracket cam is too radical for my 15 y/o daughter to handle. Suggestions? The motor's a 350 +.030, Aluminum Twisted Wedge heads, 10.5/1 comp. flattops. I haven't built a stock engine in ages. Surely there are better cams than what Chevy putin back in '84. I'll be using a single Holley 4-bbl.

i have an crane cam with 427 lift in my truck and it seems to be a real good cam i have a little lope at idle but it does not really kill the low end

Thx, Chevyman. Which Crane part#? My Lunati bumpstick doesn't "come on" until about 3500 -6500 rpm. Not user friendly for a beginning driver. Is yours' a single or dual pattern? Duration?