5.0 may only be 220 stock...but...a 5.0 stroked to a 347 or 336 can make 400-500hp. Its not so much about the horsepower to me, its more of getting that 5.0 block mounted into the car. and you can tell by the shock tower covers its an LS. I wouldnt care if the gauges worked or not. id get rid of the stock cluster anyways and go sheetmetal with some nice aftermarket gauges.
I'v been thinking about it alot latly too. Fuel would be easy to deal with as well. The big issue is the saddel tanks transfer "pump", but to be honest it would be loads easier to just get rid of the tank and do a fuel cell in the trunk. Considering track tech at most tracks, they would see a lincoln LS and not even care to look under the hood or see if the fuel cell is strapped in right.
I always thought it could be done, that guy just proved it.
I'd rather go with a chevy engine tho. cheaper to build. as far as transmissions a built world class T5 should do the job. T56 would be nice though, or even a th400 or th350.