If I just focused on the project itself about two real long days. But unfortunately I have had the ATV sitting in my shop since last fall and most of the golf cart electrical gear has been here since last winter. I am to busy to work on it and often too poor and cant justify the expenses all at once. All I need now is the three batteries and I will be able to finish it on about one more day.
The electrical control system is basically stock golf cart gear. I just need to make the wiring harness that fits it to the ATV and make the minor frame changes to get the batteries to fit properly. The rest is mostly off the shelf cut, fit, and go.
The only part that is going to be an actual custom adaptation is getting the engine temp sensor to read the electric motor. Everything engine related gets tossed and the rest of the actual ATV electrical system is so basic all I need to do is change the bulbs from 12 volt to 36 volt versions and everything else basically stays intact.
Polaris builds cheap quality ATV's and that works well for making custom modifications. Their equipment is stripped down and basic to start with! Fancy plasic body panels over a basic frame is about all they are. The mechanical drive system is standard 1980's tech.
If you can find someone that had their engine go bad, very common on Polaris ATV's, you may get a good ATV for under $500. The rest can be spread out over a year or so. And if you have even basic electrical skills a golf cart control system is bone head simple. The frame mods, motor adapter bracket, and basic welding is a no brainer too.