I'll be curious how you find the level of detail in the manuals once you've had a chance to give them a good review.
I haven't had time to review all the manuals yet, but can already tell that the AGCO Publications manuals are of a much higher quality than the Jensales manuals were. Plus, the AGCO Publications service manual is a loose leaf format which is properly tabbed for ease of navigation. A binder must be purchased separately, but I already have plenty on hand.
Despite the improved quality, it appears that the AGCO Publications service manual is also missing some parts pertaining to the Continental Z-145 gasoline engine. Specifically, it appears to be missing the parts for the lubrication (oil) system, cooling system, fuel system, and ignition system. For sake of comparison, the parts pertaining to the Perkins engines appear to be complete.
I know the missing parts for the Continental Z-145 gasoline engine must have existed at one time or another, because multiple knowledgeable contacts of mine have said so, plus the missing parts are referenced by the engine overhaul section (PART 2), shown in the image below, and highlighted in yellow for clarity. Note the upper corner which says "GROUP 0 - SECTION 0 - PART 2". Parts 1 and 3, etc... are what I believe to be the missing parts of the service manual.
The manuals arrived too late for me to contact AGCO Publications about it today, but I plan to call them Monday to try and see if it might be possible to locate the missing sections for inclusion in the service manual. Prior to ordering, I was specific about the problems I had encountered previously, but was assured that they would take all steps necessary to correct any problems that were found. We shall see.
Since much of Continental Z-134 gasoline engine is nearly identical to the Continental Z-145 gasoline engine, my backup plan is to see if anything can be found in service manuals covering tractors such as the Massey 35 which use the Continental Z-134 gasoline engine. Either way, I will get to the bottom of this, eventually.