Here's a picture update: scroll to bottom.
https://photos.app.goo.gl/h3suovzTo87XJpMW7

That body was the original ata125a body, well what's left of it from previous owner. So you did try multiple bodies including falcon mini? Darn I just ordered a falcon mini hoping with small modifications it'll fit. Guess amazon is having a body sent back to them. I'm having an issue with my wiring harness I have 2 two wire connection that were not connected, one goes to dead man kill switch and other I am not sure about. Both connectors were ran back by kill switch. Is there a way you could examine you quad for 2 two wire connectors in the rear are near kill switch and brake light and give me info which one goes to kill switch and where the other on goes. That would help me alot thank you.

Just seen your overhaul pics and wow great job everything looks clean I appreciate the fact you didn't just toss the quad and replace very honorable. It's got that ironman feel my son and I thinks it looks great.

Haha, everyone says Ironman, that's awesome.
My husband says every harness he's bought he has to re-pin it.
Are the wires you're asking about, yellow and green? If not, what colors?
Take a picture of the area/ wires your asking about.

I'm really interested to see if the mini falcon can be modified to fit. We were going to go with the falcon body thinking shrinking it down would be easier than stretching it. We still may when/if the body breaks down beyond repair. Just cutting and welding new mounting tabs, etc. I wish it was easier to send bodies back to the retailer, restocking fees and shipping charges made us throw in the towel.

I just read the part where there's 2 two wires you're looking for in the back. Ours has one 3 wire and a 2 wire in the back.
One set is the brake light, it's a 3 wire, 1 green/yellow stripe,1 wire green for ground, and a brown for the tail light.
The other is a dead man tether is connected to the kill switch which has the 2 wire coloring of 1 wire black/white stripe and 1 wire green. At the front switch connection it goes from black/white stripe to yellow.
I can add the picture of what he always has to re-pin when getting a new harness to my photo list. It's a green/yellow at the front, which is for the brake system, my husband thinks its maybe for a blinker (to interrupt the system?), anyway, it won't just plug and play, you have to take the green/yellow strip out and swap it for a red wire in another green/yellow connection, so that you have two green/yellow striped wires together in a connection and red and black wires going into a connection turning into brown and blue respctfully.

If you take pictures my husband can help better.

https://photos.app.goo.gl/nww5N1VXMbLi829UA I have added a link that shows two 2pin connectors (wire harness) that run towards the back of atv. One Red/Black the other Blackwhite/Black. One is for the Dead man switch other is a mystery. The second photo has the two 2 pin connection that go to the other two. One is the Dead man switch (red/black) other is the Mystery (greenyellow/black) was cut before in my possession. This Mystery wires run almost as long as the taillight connection to the back. ( My tailight is also 3 wire and same color as yours)

I am leaning toward the dead man switch goes to Blackwhite/black because the Blackwhite run to my handle bar switch like yours. Still have no idea what my mystery component was

My husband says that your mystery wire has to do with the tail/brakes/turn signals. Yours must be the original wiring harness, he's seen that before where black is the ground (in the updated harness they're green). He says hook up a test light or a meter to it and hit the brakes. It should do something. He also said look at the rest of the forum, there's threads with the wiring schematic for our quads on here somewhere.

Yes, to the other one being the dead man switch.

Definitely will have to do when I get it back together, thankyou for your help It reassured me about a couple things. I'll stop by an update abs I go. Thankyou.

Did you happen to try the coolster 3050 plastic that you linked on 8/16?

No, we didn't try any other bodies. Sorry.

Anyway, here's the final-ish product!
https://photos.app.goo.gl/h3suovzTo87XJpMW7
He loved it. :)

Wow... really nice job on that!!!