I never took a second look at the NV3500 because it has an integral bellhousing... the 4500 was eazier to adapt. I believe I have one in my 2004 wrangler, and it shifts pretty well, but is a little noisy in 1st gear.
The NV3500 is a lighter duty transmission probably pretty similar to the t-5 in capacity and gearing.
The NV4500 is a toploading 5 speed with the shifter being about 10 inches from the front. It would move the shifter back about 3-5 inches from stock for the sm420 and other toploading 3 and 4 speeds.
