Fergie Questions

Hi Guys.
1) On my grey Fergie (which is actually yellow ) I've found the VIN number and the engine number, BUT on the left hand side of the data plate is stamped vertically into the body (not the plate) the numbers 9300.
What does this indicate?
2) Someone advised that there should be a heat shield between the exhaust manifold and the fuel tank.
Was that standard, as I have never seen one?
3) Anyone heard of this remedy for leaking seals?
I saw that many years ago. An old farmer had a TEA-20 with leaking axle seals. At the time no money for the repair (changing seals) and no time to send it to the dealer...tractor was required for hay time and other chores.
His son which was at technical school on a holiday break decided to drill tap and install grease nipples at the end of the housing 3~4 inches from the back plates. He then injected some very very thick grease with a grease gun in order to stop diff oil to reach the seals. Believe it or not it worked...oil stopped to leak immediately and lasted several years without leaks.

Thanks. Rod.