[pairodice]

I would call Newell FIRST... I have been surprise a few times when I talked to the guy that built our coach! This sounds like a leveling valve but not sure which system your coach has - I would assume they are similar... As I recall Newell said the coach should ride about 8 (I think) inches from the bottom of the coach just behind the rear wheels. I don’t think it will hurt anything to be too tall but call them in the morning just to be sure... remember they are closed on Fridays!
Would love to see pictures inside your coach! Hopefully it still has the original orange and brown shag carpeting! :-)