Merry Christmas..I noticed your question pertaining to LED Lighting for JD X540's. I own the same tractor and have found LED lights for the rear tail light lens's. There is a gentleman in New York by the name of Jeff Walters that takes the stock X540 reflectors, drills them out to accommodate three LED lights in each tail light lens. His e-mail is jefflhs@hotmail.com
I think he charged me $125.00 for the pair which also came with a wiring harness. I gotta tell ya that it was just PERFECT! He did a GREAT job on them and they look AWESOME when lit. I was just out using my 47" snowblower on my x540 and a township snowplow drover stopped (also owning a 540) asking about the tail lights. Send an e-mail to Jeff and he will help you. I hope that this helps and that you get them and enjoy them as much as I do. Now, I'm trying to find LED Lighting for the dash! Who would design a tractor with headlights (anticipating nite operation) yet provide NO dash lights so you could see your fuel level? Really dumb! John Deere messed up there!