Simplest would be what you suggest to flip the axles and then use the higher mounting hole. If I understand your concern, the side of the spring would rub against the hanger bracket...but from the picture, I can pretty much guarantee that's happening already as you go down the road, so the upper hole shouldn't make it any worse. On the positive side, being closer to the frame should make the hanger stronger against side to side forces.
But really once you go thru the hassle, I would just do the flip by itself and try it for a season. You can always change the mounting holes later.
Another option if there is enough room in the wheel wells is to mount bigger tires. You could probably pick up an inch or two that way with no other modifications.
If you want to throw money at the problem, you could add airbags with a remote air fill compressor connected into the cab. Any time you are worried about clearance, just pump up the bags then release once you are back on the highway.
No, it's not a concern of leaf spring contacting jnside of hanger, rather, it the shackle and equalizer hitting the hanger specifically center hanger. Take a look at these pictures, circled in red is where I already get some light contact. Hanger is about 4" wide at contact point and widens to 5" at the top. Moving to upper mount will shift it to an even wider point and more contact.
I already went one size larger on tires.
You're correct I could just do the spring over and not mess with changing spring mount locations.
I would have to go check but on mine but I'm pretty sure the center bracket is shorter and squared off. The two outer ones have the angled cut.
You could cut of the angled one off and weld on a shorter square one.
If I can do this without welding on the frame, I'd prefer to. Another thought I had was to simply cut the existing angled hanger into a rectangular hanger. No welding involved other than spring perches onto the axle for the spring over.
Actually, nothing rocket science about the hangers. I'm betting any moderately competent welding shop could bend you up some custom hangers that are 2-3 inches taller and weld them on. I would look at welding plates on the ends to stiffen them against side to side motion. Alternatively, weld heavy square tubing to the frame and then weld a stock hanger to the tubing.
This would allow you to specify the exact height you want to raise the trailer by and the rest of he suspension doesn't need to be changed out.
