Want to add a battery disconnect switch to a john deere gator but can't find one that will fit the battery terminal. Any suggestions?

SOURCE: old john deere gator and battery new charger still will not move

Could be several things.  Your battery could be bad. After not being charged for a while, they do go bad- often. You may want to try a new battery along with your new charger.  You could also have a switch /connection problem. If you get a new battery and it still doesnt work, you may want to check the switches and wiring. It is not uncommon for the switch to go bad especially if it had been stored outside. 

SOURCE: John Deere Gator 4x2 - Left Wheel doesn't move when in 2nd gear

I would replace the high/low switch and the reverse switch. One time a replaced the high/low switch and the reverse switch quit on me 2 weeks later.
You can also get the Peg Perego Gator Shifter that upgrades the vehicle.
You can get the parts and repair help at this site
http://www.shopjandl.com/kids---baby-ride-on-toys-peg-perego-switches-and-shifters.html
They have helped me several times.
Hope this helps

SOURCE: John Deere Gator not responding with new battery.

I upgraded my Peg Perego shifter and it came with the wiring harness.
I bought it at http://www.shopjandl.com/
Hope this helps.

SOURCE: battery is charged but car is still not working,

I have the switch go bad on the gas pedal. You can find a replacement here http://tigerimports.net/sunshop/

SOURCE: help for my childs John Deer Gator

the peg perego gators have two switches in the shifter that need replaced.
I have replaced them before on my grandkid's gator.
Here is the website I get my parts from
http://www.shopjandl.com/kids---baby-ride-on-toys-peg-perego.html
You can also call them direct at 1.801.655.0800.
They seem to always know which part I need and I have always been very happy with their service.
Hope this helps