Any mods or trailer builds after 2012 (February I think) have to go through a VOSA trailer approval test.
If your trailer has a plate on it check the date of manufacture. I’m not condoning this lol but if your trailer was manufactured prior to the 2012 regs you may have modified it before the regs came into place
If it was me with your trailer I’d be going down the box section insert route rather than a bolt on visible mod, chances are done like that it’ll not look out of place and it may well fit in the approval of the manufacturers spec anyway.
I know when I questioned the length of two trailers prior to purchasing mine, the only difference was in fact the draw bar length.
I see no reason why you can’t remove the draw bar from your trailer and replace it with a longer section of the same spec/size steel. Bolt through in 2-3 places using the original holes and Bobs your aunties uncle.
As said, this is what I would be doing if it was mine and I couldn’t possibly point you in the direction of anything illegal, so please take my comments with a pinch of salt.





