Has anyone successfully used the USCartool A500 Crossmember?

yes, I had the empty case bolted in the car, to the engine. You can see it in the pictures.

Great. Thanks. I read a ton today about pinion angles. I'll pick up that angle finder and measure the pinion angle and then figure where the trans needs to be.

From what I read, the driveline needs to be paralell with the crank at wot. The pinion will move up about 3* from where it is when the suspension is loaded. So if the pinion is down 3*, the trans will need to be 0* (just an example)