Advice needed on Oliver 1650 project tractor.

I am a "hobby farmer" as I"m too lazy to farm fulltime, and am looking for a "project tractor". I currently have a 1954 Allis D-17 I built out of a two tractor pile of parts, and it has been a good tractor for 8 years, but has some limitations. I rebuilt the D17 engine from the crank on up and it is fine from a horsepower perspective. The problem is the hydraulics,slow shifting and just generally being a clumsy machine.
Anyway, what do you guys think about an Oliver 1650 project tractor? From what I read, a rebuilt one would be a good machine for my needs; great design,better hydraulically, good hp, shift on the fly etc. I have no issue rebuilding from the ground up, although I"ve never rebuilt a Hydrapower drive. Is it like rebuilding an automatic transmission?
Looking forward to a fun project and will take all the advice I can get!

Here is a picture of what my 1650 project looks like at the current time. I'm working on setting the axle preload right now since this gal is getting new bearings all around.

The fun part will be working on the engine. I said the heck with the Waukesha and will be mating up a brand new Cummins 4BT. In the end, I will be saving around 1 gallon an hour in comparison to the original diesel plus I was able to buy a brand new Cummins for less than I could rebuild the Waukesha from the ground up. The challenge will be to make everything fit without turning it into too much of a cobble job :P