Dreaded

I reread your post and you say the starter solenoid does click when you try to start it. That indicates a bad starter solenoid. The contacts do go bad often in those and most like will be the cause of not starting. Some machines do not have a neutral safety where it has to be in neutral to start. The indicators lights will be the wiring or the switch causing the problem with the lights. Do an online search and there are videos that show how to replace that switch and where it is located.

As to your reverse light staying partially on. I would say that switch has gotten some trash in it that is passing ground through it.

First thing I would check is the plug connecting the shift position indicator switch or neutral indicator switch This depends on if the machine has a multi-function position switch or a single switch. It is supposed to close the switch to ground to turn the indicator on and it should also act as a safety switch to prevent starting if it is not in neutral.

This acts like you have a shorted wire going to the shift position indicator switch, a bad connection in the shift indicator wiring or a bad shift position indicator switch. Since it doesn't light the neutral light the indicator switch or wiring is not making the circuit and so it will not start without in showing in neutral.

Page 302 in this manual is the start of troubleshooting the ignition system.

To start with the voltage to the coil is a capacitive discharge voltage not a dc voltage. The basics is the CDI (capacitive discharge unit) operates off the magneto generated voltage and a pickup that tells it when to fire. The capacitor discharge unit charges up while the magneto turns past the charge coil and then fires the coil when a magnet passes the pickup coil. If you are not electrically oriented, you will have trouble repairing this. Here is a repair manual in case you don't have one. Follow the troubleshooting procedures in the manual. After you familiarize yourself with the manual if you need help I will help you. hs500utv.pdf

I decided to tear it down since it took a couple days to get site approved. What I found is the clutch melted and froze. Pics show it all. I took the clutch apart and found clutches jammed up and not movable. I ordered a new secondary clutch to replace it, the primary drive seems ok so I will reused it.

This tboss 410 started having a problem with I think clutch not releasing. If you have it in forward with neutral safety disabled and try to turn it over, it will try to move forward. Neutral does work correctly. What I was told occurred was he was trying to back up a hill and was trying to pull a load. He said that it all of sudden died and would not go into gear. To get it back he disabled the neutral safety and started engine and drove back but had to switch to neutral to stop. Is this going to be the centrifugal clutch on the drive belt or could it be something else?