Congratulatons!
Check the serial number!
A D6 9U won't weigh that much without a blade, and it doesn't have a power reverser. Bare tractor is ~18,000# and it does have a reverser shifter, but it's strictly manual.
From left to right you have the main clutch, left steering clutch, right steering clutch, throttle up on air cleaner (pull it to speed up, push it to slow down), 5 speed stick, and finally on the right side you have the reverser, push it forward to reverse, pull back to go forward.
Reverser works in everything but 5th gear, either way you shift the reverser, you will still go forward in 5th. In 1-4, reverse speed is slightly faster than forward speed.
D2-5J's, D6-9U's, D318 and D333 power units, 12E-99E grader, 922B & 944A wheel loaders, D330C generator set, DW20 water tanker and a bunch of Jersey cows to take care of in my spare time😄