I was going to flatbed my '19 3500 Tradesman until I read the fine print on my 8yr./125K Maxcare warranty. It specifically spelled out the bed delete trucks and flatbed equipped trucks weren't eligible for the warranty. I don't know what happens to the standard warranty, though. You do you, I decided against messing with it.
I ordered a 2017 3500 cummins. Registered in ca. Then removed the box and put a flatbed. I didn’t encounter any registration issues.
I have sold that truck and ordered a 2020 3500 cclb, will again remove bed and install highway products flatbed.
jsalbre is right, on both accounts. removal of taillights and your cross path detect/bsm will not work. Can prob disable sales code to remove any error messages on dash. I’m not too concerned with bed removal and warranty issues.