Yes,sometimes ignorance is a bit spendy. I have owned many trailers and many spread axle trailers. As a general rule my closed tandem trailers have a 36" kingpin setting,but on my spread axle trailers i set the pinsetting at 24".This makes them easier to make proper weight distribution.Once they hack of the back 3' and move the axles its only a little more money to move the kingpin....what the hell....it only money...WOW.
The KP doesn't have to move.
This is not a reefer where you have pallets of heavy freight on the drives.
The only thing over the drives on a race trailer is the weight of the genset, and the lounge, which only has a couch/desk/closet amd maybe a dumper. Not much weight at all.
That's why cutting three foot off the back and moving the rear liftgat up isn't that big of a deal to do.
But probably easier said than done..