Have you considered having Kubota look at it? It may be a switch issue that is causing the over sensitivity of the switch. A simple change out might fix the issue.
Most people opt to just delete the switch, and while I admit that the switch can be a pain at times, there is a perfectly good reason for it's existance. Most people don't think the rare occasions that the switch might save their lives to be worth the aggravation of dealing with it.
My biggest issue with it is when I am trying to pick up something with the forks on the FEL and I can't quite see the tips of the forks, and don't want to run into the item. I typically get close, then adjust the for tips by standing up to see them, then moving slightly forward till I am under it. Not possible with the switch operating.
Just for the record, I have never disabled a switch, and my Kubota doesn't shut down when I get off the seat, so someone must have!
David from jax