Question on rgn adjustable ride height valves.

I want to make the rear axle on this trailer a lift. The trouble is when it's empty the amount of arch it has, coupled with a very small amount of suspension travel means I can barely get the back axle off the ground with the ride height set proper.
If I can adjust the ride height up to the upper end of the range it ought to work for running empty. I've never seen an adjustable valve tho. I'm thinking the air line plumbing is still the same and it's just got some sort of lever on the side that changes its guts internally?
I do a ton of deadheading and empty this thing wants to twist on that rear axle all the time. With 47' from the kingpin to rear axle she turns like a pig.
Anybody got a trailer with an adjustable valve that might retrofit let me know so I know what to look for. Thanks.

 

Thanks. I ran across that one doing some research.
I'm looking for more of an infinitely variable one.
The trouble I ran into was originally the leveling valve was mounted on the rear axle. With the 12' spread and arch this things got the back bags would be around 25% off full travel, and the front at 75% to get things right.
When I had this mid 60k press on it took the arch out. The trailer didn't go negative but my 5th wheel is a bit lower so normally loaded the deck is 2-3" lower at the neck than over the rear.
With the front sloped down a bit the front axle was almost bottomed out. I had to raise the ride height rod to compensate. Then empty it was reversed. Front bags fully raised and the rear about half.
This trailer just doesn't have enough suspension travel for the amount of flex built in to it.
Since then I moved the leveling valve to the center axle to get more of a average between the 3.
That helps a ton but to be able to twist a knob to dial it in would be great.......
I'd really like to find one off a name brand trailer, so if it ever goes to heck on the road I can find a new one easier.

 

I'll be danged. Reitnouer has a factory valve......
Big thanks.
Move along, nothing to see here.....
I'm just a dummy.....