Hmmm, the plot thickens a bit. First, the serial number on the hulk Cockshutt (brass engine plate) is 411499 which in my book here says is a '47 Oliver 60 but those serial numbers applied to both Oliver and Cockshutt 60's right?
You mentioned it being a 66 engine, I don't see any 66 serial numbers that low with 42XXXX being the lowest starting point for 6-digit 66's (of all wheel versions)with 66 Supers only having 4 or 5-digit serial plates.
Trust me, both "tractors" (forget the engines) are model 60's, the Oliver is inside the shop here and the parts Cockshutt is outside, the engine was pulled out of it last week.
On the rebuilt Oliver engine (that needs a spacer), the cam & crank timing gears protrude out past the front surface of the engine block so the spacer is needed, no getting away from that. The aluminum timing gear cover plate is identical (pretty much flat) on both. The Cockshutt engine here does not need the spacer since the block is out past the timing gears (which are recessed).
And as I mentioned, the height and length of the blocks are different. Next time I'm there, I am going to get some measurements.
I'm wondering why the diesel engines would have the spacer? Did the 60 series come out with a diesel option?
My email address is ... firstname.lastname@example.org .... so if you repy with an email directly, we might be able to communicate a bit easier and eventually solve this. Thanks for the help so far ..... MIKE