Does your tractor have draft control? If so, is there a second lever for the draft control next to the lift lever? If not, then it could be the on/off for the draft control?
You could pick up a used Swisher mower and replace the engine with a vertical-shaft engine that has a pressurized oiling system.
I use a Swisher pull-behind mower on my yard and have a few areas where the mower is angled a bit without any problems with the stock engine over the past 12 years.
When I had my Ford tractor (before Kubota), I found an old toolbox at the dump, painted it up, and mounted it with rubber spacers to the fender. It worked great for holding extra pins, a short chain, and a few tools...