Kubota L2650 Wont turn over

With a recent cold spell/snow there wasn't enough juice in the battery, and I had to jump start my tractor a couple times. The last time a couple days ago, it started fine no jump start, and I put the charge on for a full charge on the battery.

However, today it would not turn over, either with just the battery, nor with jumper cables attached. One of the terminals was loose, and i tightened that up. When I turn the key to start, No click or anything, bright lights on the dash, headlights bright. When I turn the key to the left, it clicks or makes a noise on the solenoid or something in line with the ground post on the battery.

I am wondering if a relay is out.

Checked the 5 or so fuses in the fuse box, none burned out. HELP please.

Any suggestions or tips would be greatly appreciated.

Thanks in advance.

Does anyone have a diagram of the location of the safety switches on a 1991 L2650 Kubota. I fiddled with it today without success. I know that it has to be in neutral to start, assuming the PTO has to be disengaged as well. Fortunately no new snow predicted as I am waiting for parts for the snowblower too.

Update

Thank you to those that replied and offered suggestions. The culprit was the safety switch on the forward/reverse shifter. I believe the other safety switch on this model is associated with the pto, as the seat does not have one. That being said, I am back in business...let it snow. I suppose now I should tear down the snowblower and replace the broken impeller. When it rains... it rains.