Using the wheel opening to measure is stupid . the wheel openings front to rear are not the same distance from the ground . Put a spirit level on the rocker panel .
To lower those front ends kind of easy you swap in a set of lower control arms of a similar year van. They have a drop spring pocket in them that lowers you an inch or two. You have to trim them slightly and drill some holes out for larger hardware but I can't remember exactly what now days.
I remember reading back in the forum days that was the best way to lower them affordably, good to remember for the future because I’ll eventually upgrade it.
