I used a carb'd 75 Mexican Block in my 1973 240z. Wiring is super simple this way and lets you focus on the rest of the swap. I built my mounts using Brian Laine's drawings as references and used JTRs transmission mount. If you search my name, I posted google sketchup drawings of my mounts...very similar in design to Brian's, just modified a little for the engine mounts I wanted to use and how I wanted the motor to sit.
The process I used for making my mounts was like this:
-Lower the engine and transmission into the car
-Back the motor up to the firewall as close as you can (mine is about 1/2" from the firewall on the driver's side) and focus on getting the transmission where you want it and make sure it lines up nicely with the diff and shifter hole
-I would have the headers attached at this point and make sure you have clearance with the steering column as well (my motor is canted to the passenger side ever so slightly because of this)
-Drill the holes and mount the transmission
-Now focus on the motor height and angle using the hoist
-Once you get it where you want it, I used some thick cardboard and mocked up 2" square tubing. I used this cardboard tubing to make a cardboard mount that fit exactly where I wanted the motor to sit
-Measure your mock-up and build that bitch with 2" square tubing and angle iron
Obviously there is more than one way to skin this cat, but I found this to be the easiest when I was going through this process. If I were you, I would buy Brian Laine's kit, the JTR transmission mount and a bottle of Woodford. You could have the motor and transmission in the car before the second pull of the bottle