I am glad that you found a welding shop that can do the work for a reasonable price. My last two tractors had folding ROPS but I never utilized that feature. I am fortunate that I have enough clearance to store the tractor without folding it. My main reason is that I utilize a sunshade. The summer is brutal here and without that sunshade it would be unbearable. I wonder how many folks with sunshades or tops fold their ROPS? Looks like it would be a pain in the rear.
They didn't powder coat, I ended up scuffing everything down and shooting it with flat black. still have to buy some pins for it. They gave me 3 adjustments for folding.
I'd just shorten it to fit underneath your doorway. Cut out a section and reweld.
I don't use my folding ROPS because the 1 and only time I did, I bashed into the top of the garage doorway and did some damage. It folds at about head level. That's where it stays. The FEDS should get smart and make them just less than doorway height on all the smaller tractors, maybe < 32 hp.