ABANDONED John Deere M Revival Part 2

Today we are going to rebuild the 1951 John Deere Model M's carburetor and we are going to re-seal the hydraulic pump.
The carb rebuild includes a stuck main jet complete with broken main needle value. I tried left handed drill bits and extractors but nothing worked. In the end, it took drilling the main jet out and tapping the threads. The hydraulic pump re-seal goes pretty well except for forgetting the casing seals and having to take it back apart to put them in.
This is the later model three piece hydraulic pump. I don't know why they went from the two piece to the three piece pump but my Granddaddy's 1950 had the two piece and this 1951 has the three piece. There was a retro fit kit to go from the two piece to the three so I'm not sure if it came with the three piece or if it was converted later.