When I ordered my axel, I had to specify what the angle of the torsion arms would be (I got a Dexter). I took measurements of the hitch and the wheels & tires, so I could estimate the frame height and which torsion angle I wanted.
I'm getting ready to finish up the welding on my frame, and mocked it up to make sure that it was all level.
It all comes out fine on the VW if I stack the tounge (double it up, with the top piece holding the coupler), which isn't how I originally planned it but that's fine, I've done that on other trailers to get the bed height down. The frame has plenty of ground clearance (especially compared to the VW), and sits level.
My concern is, how it will couple up with other vehicles. The flat part of the VW hitch (the plate that the ball bolts through) is 13 1/2" from the ground. My other vehicles are both pretty tall (both 4 x 4's), and the hitch on them is 3-6 inches higher. What is the average hitch height? I hate to build this trailer and it only be good for a VW, since I know that no one is ever satisfied with their first tear, and goes on to sell it and build bigger and better trailers.
I have a couple of options if the hitch height is too low. I could leave the tounge straight and add 2" spacers under the axel (double up the frame where the axel mounts). Then if the tounge was too low if and when I decided to get rid of it, I could stack the tounge, and gain 2". Of course, this raises the profile and the entry height, which I want to keep as low as possible.
The second option is to bolt the axel on, instead of welding it. Then, if I decided to sell it, and the buyer needed the extra height, I could swap the axel for one with a different torsion angle, and possibly use this axel on my next tear. The only thing I don't like about this option, is that I feel safer with the axel welded on. Bolting it does have the advantage of being able to swap it out easily in case it was ever damaged.