nope. we went with the stock 5.0L mustang harness, mustang computer, etc..Hell, I could run airbags if I want to..the wiring & harness is there ... ran a Electric fuel pump and return line. the electric fuel pump uses the stock harness. Alternator light in dash works. TEMP light in the dash works. Essentially, all the factory warning lights work in conjunction with the computer.

we had to extend the wires for the 02 sensors. they're custom installed on the H-pipe after the header. it has a "clutch fan" from a Crown Vic: when the temps get up, it engages the clutch to suck air through the radiator.
..
the car even has a check engine light. We pulled the codes and the only ones being thrown currently is the "EGR error"
we need to change the gaskets on the TB and run a vacuum line and that will resolve the issue and increase the MPG.

I retained the stock C4 trans and stock rear end. I had the C4 rebuilt (for no reason as it was perfect on the inside after dis-assembly) as a piece of mind and we added a B&M shift kit to it.

stock trans, stock shifter
3-speed love
peg-leg tire spins

the cam wakes up at around 3500 rpms...no rpm gauge so I couldn't tell you when it occurs. 1 5/8 primary headers to 2.5" exhaust, mandrel bent to a set of 40 series Flows (i think).

I'll have to upload some pics..Hadn't really thought about it because the video of the exhaust/CAM is killer!!!

Big props to my Bro and and his buddy Shane. both figured out how to do this "swap" on Shane's '66 Fastback except Shane's is running a 351 CI w/ Twin Turbos....

I'll answer any questions you ask..except for where I live and vin number & tag numbers

Joe