[fixwheelmad]

If your springs aren't becoming loose or dislocated when you jack your van up, I personaly wouldn't bother with shortened units. I would look for a good quality heavy duty gas charged set.
I've had 4 different sets of shockers on my van last year trying to get the thing to ride how I like. From standard to now Projektzwo (Bilstein B6s). I've found the rear end never seems to change much in ride or control from make to make with what I fitted, but the front has varied quite a bit.

can you elaborate on your current set up, very interested in what you have found, regards