I have a 76 with out the power booster as well, so don't use that. I have a 74 as well but haven't had the original steering column in it for over 25 years. My 74 had the large distributor cap which could have been added later. These guys are really good at picking up small details.
See if he'll send you a pic of the tag on the glove box door, or better yet the tag on the drivers door post. or VIN number.
I have sent a request for this info to the owner, I need it to arrange the insurance on the thing for when I haul it anyway in 12 days...;D oh yeah the count down is on!