I need to get all this through my firewall,
1. Boost controller cable
2. msd btm control **** cable
3. two 4 gauge cables to relocate battery to the trunk.
I've found one small hole under the fuse box in the engine bay. Are there any other holes I'm not finding? I hope I don't have to get the hole saw out.

 

I ran a 1 gauge cable through the stock grommet on the passenger side of the firewall (just stuck a wire hanger through it, taped the cable to the end, and pulled it back out). I have my boost controller power cable and vacuum line, and sensor lines for several gauges running through a hole i drilled by the clutch pedal, right below a hole that was drilled for my alarm wire. Its pretty easy to drill a smallish hole here and it comes out of the firewall under the clutch reservoir.

 

Just remember to sand the hole to get rid of any sharp edges...and put some kind of protection around the bare metal so you don't ground any power wires. Can you say BURNT UP CARPET?!