Ron, I'm one of those people who disagrees with lowering your t-case. First, you're giving up some of that precious ground clearance that you're trying to obtain. Second, by lowering the transfer case, you're placing a constant downward tilt to the rear of your engine. This can place stress on motor mounts, and it can interfer to some dgree with the gravity fed portion of the engine oiling system.

If you wind adding enough lift where your rear driveshaft is vibrating, a far better solution (in my opinion) is to take your driveshaft in to a driveshaft shop and have a CV joint (double cardan joint) installed at the front end of the shaft.

There are a lot of people who have lowered their t-cases, and they'll probably feel that I'm being overly cautious, but that method has always worked for me.

By the way, you only need about 4 inches of total lift to run 33" tires on a CJ7