I don't know what brand of light fixtures you have but for my TT, I found LED replacements at commandelectronics.com. Later, another friend turned me on to some less expensive replacement kits from eBay for around $5 each. Made in China but they work well.
Mike, Sue, Sissy and Little Man
2015 Ford F350 Lariat FX4 6.7 CC DRW
2015 Eagle Premier 351RSTS