thanks for the responses guys !
i forgot to mention, when the key is turned to start, the solenoid clicks and you can see the starter gear jump toward the ring gear, but the solenoid wire at the starter is only receiving 5.22v, thus acting like a dead battery, just enough volts to excite the starter, but not enough voltage to turn the starter motor over,
when a full 12v is applied to the solenoid wire, either by jumping the hot lead at the starter connection to the solenoid, or applying 12v to the solenoid wire at the timer module [where the 5.22v originates], the starter works as it should.
that leads me to believe the tractor battery is good and the safety switch[es] are working. i would think if any of the safety switches were bad, when the key switch is turned to start, there would not be any voltage [no matter how low] sent to the starter ? i have the starter switch hanging, and it puts out 12v in both the run AND start positions, while in the run position, the start position has NO voltage present.
i did a quick check of all the fuses at the beginning of this ordeal, but i will go back over them to see if dumazz me missed something.
i also have jumper wires made up to bypass the safety switches.
as i have said, this is my first go at a diesel tractor, so i know nothing about it.
i hate to spend anything on a factory FSM to never use it again. if it were my tractor, i would have bought one as soon, or shortly after, i bought the tractor.

thanks again for the suggestions guys ! please keep 'em coming !