L2350 4WD, Starting Problem (Electrical)

Hi!
I'm new to this forum, but I read thru all available posts before signing up. Tractor is a L2350 4WD w/ LB400 Front Loader Bucket...actually this is my Dad's tractor.
The tractor will not start.
Tractor was last started and run at Thanksgiving. Next time tried to start it was a week later. the weather had turned and temperatures now below freezing.
There is no electrical activity at all.
No clicks from the starter solenoid.
No lights, no glow plug indicator, no sounds.

I have the electrical schematic and myself have cleaned and checked the battery connections, fusible link and chassis ground and the hot connection at the starter from the battery. Also removed the ignition switch brought it inside, cleaned contacts and verified switch operation. I have also cleaned the contacts and verified operation of the safety switch (clutch operated). There is no Seat safety switch, and all levers have had their position checked before attempting to start the tractor. I have cleaned and inspected the harness and connectors to the Ignition & Combination switches. Still nothing!

Any suggestions would be appreciated!
-Todd

Success!
Thank You both; TD and Wolfman!
After proccess of elimination I was thinking the battery was the only thing remaining. I did "sort of" check the battery before checking everything else... I had the charger on it and it said the battery was full. My dad bought the battery this past spring, so after a quick check I moved on to other things. It probably needed the electrical grounds and connectors cleaned anyhow as this tractor is covered in mud and lives outdoors without even a tarp to protect it from the weather. I am not my father! I have urged him to keep the tractor clean and covered if not in the barn. My post was seeking anything electrical that did not show in the schematic. Instead your responses just verified my suspicions...a bad battery inspite of being relatively new and showing fully charged. We jump started the tractor and now have replaced the battery. Thank you! Thank you!

Forgot to mention that even after the tractor was running, the lights did not work...none of them! I checked the fuses while tracking down the starting problem, so that is something else to look at...in the future! This little Kubota doesnt go off the property nor does it get used at night so this is not really an issue.
Again, I really do appreciate the input I got!