A warning and maybe a prayer would help

In my line of work I run into hazards left by "the other guy" all the time. Bonding, grounding, suction entrapment, explosion, asphyxiation, ect. If it's something small I just fix it and move on. If it's something more involved I make the customer aware and provide an estimate. If they don't want to fix it I make them sign off that they were made aware and refused to fix it.

I agree with what most of what has been said here.... but the original poster did say, The owner of the vehicle and his mechanic dropped the vehicle off at " 1930s shop, so with that being said, did the mechanic do all of the driveline work, including motor/trans combo?? If he did, I would assume that the mechanic could be sued first, for not seeing thru that any safety features be done and finished correctly, and that is the mechanic's responsibility, PERIOD!! As far as the OP, when he found out about starting in gear, throttle stuck wide open, he should of, IMO, disabled any control etc, that would let it start!! I
still think that most of the blame, should bear down on the mechanic! Anyway's, will pray for Tom's full and speedy recovery, and will hope he get's the beautiful chance to drive his dream truck, fixed safely and properly.