I tryed to keep my carb base level.Trying to add weight to front and rear to simulate a completed car.Even if you get it exactly level now adding or removing spring leafs later to fine tune the ride will effect engine level.I don't see it as trying to be exact but close.The worst thing I ever bought was a digital level as I try to get it exact Others may chime in with a more better formula.BTW good looking chassis
Pete,
You want the longitudinal centerline of the crankshaft to align with torque tube centerline as close as possible. Should be a straight line from center of crank pulley to center of differential. Some guys say if you set the centerline of the crank pulley with the original hand crank hole on the radiator shell, you will be very close. The Tardel type front motor mounts place it exactly in that position vertically.
The crank in line with the driveshaft is a good plan, BUT, the height of the engine will have a lot to do with how the car handles. If you plan on doing any hard cornering at speed, you had better do some studying on chassis setups.
I tried to get my water outlets on the radiator and pumps as close as possible, the trans end was a K member/32 frame, so no adjustments made there other than distance from radiator for fan clearance.