Can you post a picture? It may be easier to lower the front than raise the rear
It's very, very difficult to get to the rear adjusters with them still on the van. I have B14s and the principle for adjusting them is the same as yours. To be able to adjust mine I got the van up on axle stands, released the bolt from the bottom of the shock on both sides of the van and then dropped the springs out. That makes the adjusters easy to get to and you can wind them down a bit to increase your ride height. Then reassemble in reverse. On my B14s the rear spring is still under some compression when the shocks are fully extended, so in order to stop the spring thumping the rear arms into me when I undid the lower shock bolts, I supported the rear arms on my trolley jack. After removing the bolt I slowly lower the jack so that I had control of the process until I had enough room to remove the spring.
I had a problem with the rear springs on my Stance+ Ultra kit being almost fully compressed, resulting in a stiff ride that would sometimes seesaw over bumpy roads. I got on to Venom Motorsport and they sent some taller springs out. I had them fitted and the ride is better.
