I had a brain fart last night & figured out what to do. I stopped by the RV shop today where my trailer is having some wiring done & took measurements.
All I need to do is move the twin gas bottles back about 10" - 12" & then relocate the jack to sit right in front of them. While I was there taking measurements the Foreman happened by & I explained what I needed so it won't be a big deal.
The twin bottle holder is about 24" wide so they'll weld on a flat cross member & mount the holder to that. Another tapered cross member will allow the jack to be moved way back & my troubles are over.
Dunesport used an A-frame ball coupler that already had a hole for the jack so I can't fault them. I have a good repoir with their Sales Manager & they've incorporated a couple of my previous suggestions. I'm a retired Mechanical & Software Engineer & did a ton of new product development & inventing during my career so I'm always looking for ways to improve things. I joke that I have a disease called "Modificitis" - I can't leave anything stock - I have to change it somehow.