I bought a used boat a while back. Great boat BTW. bought it from a forum member. The question I have is on the trailer. I only has left and right stop/turn/ license plate lights. Haha. That work are are not missing. The boat is a smaller boat, a Nitro. The trailer has three center marker lights between the tail lights that do not work. And also has/had side amber marker lights. One is missing. One doesn't work.

So, by law, WHAT is required? I have towed it a lot in the dark with the shorter days. Just don't want to get busted. Or look like a fool.

You can remove the 3 light bar between the tail lights but you need to get all others working. If a light is on the trailer it has to work.

i only have two tail/stop lights and my trailer is under 4500 lb capacity, so no inspection.

Inspection or pulling down the road it is the same. I would prefer not getting the side of my boat and trailer clobbered. At minimum 2 amber side clearance lights on each side and a rear red side light for me. PS cross your safety chains.

Maybe, maybe not. I think the need for those is determined by load width. At any rate, If memory serve me, if the width of your rig, boat and trailer is 80" then the three light bar is required. There may also be regulations on having certain side lights for specific configurations. I would go to TDOT website nd look up the light requirements. At any rate, I would be sure before removing anything. The regs are easy to find and you never know when you might pass some trooper with too much time on his hands.

Edit:
Here is a PDF that gives all of the light requirments for the different size/configurations.

Your trailer was probably built by a manufacturer to cover the laws of any state it may be used in, but even if you are not required to have something that is on your trailer, no one ever got hit because they were too visible. Do whatever it takes to restore it to factory condition and go cheap on something else.

https://www.txdps.state.tx.us/internetforms/Forms/CVE-38.pdf

The PDF doesn't refer to it, but I did find a couple of sources that say a trailer over 80" wide must have the three ID lights on the rear. That's only 6.5' and I think you would be hard put to find a boat trailer less than that, so I would put the lights on, again, like the trailer came from the factory.