There's a lot of little stuff that can get you, like for example if you order a strange driveshaft, you need to either adapt 1350 U-joints to 7260 or 7290 or swap the yoke (which I had done previously to my swap, I have an 8.75 with a 742 center so it was easy but still). Hoses, bolts, AN fittings, sheet metal for floor patches, welding wire, welding gas, etc, all adds up. I think I used about $50 worth of CO2/Argon to do my swap since I have a pony tank and I used basically an entire tank on it.
Also think of the speedometer, connectors, reverse lockout override, etc. I had an electric speedo already, and I have megasquirt so the reverse lockout was just a program in there, a relay, and some wire. If you have a carb you either need to make a push button for it or to buy one of those "boxes" that reads the VSS output to do it for you on the T56. It's just a solenoid anyway.
