HP Z3200 rev A vs B

[PrintSmears]

Hey all!

I purchased a supposedly complete used Z3200 from a very bad person who seemingly swapped a bunch of parts around on this printer. Because of this I have no idea if this is a rev A or rev B printer. The sticker on the back says Q6721B which would lead me to think it's a rev B printer, but it has a rev A formatter in it from what I can tell. The formatter doesn't have any lights near the ethernet port and the hard drive is mounted to the center of the board...if that helps anyone. Also when I turn the printer on and go to the printer properties, it thinks it's a Q6721A

So first question, which parts make a printer rev A or B? The formatter? The printmech PCA? The mainboard in the PSU?Which parts need to match up? How do I identify which part number are rev A vs rev B? I have the service manual and it doesn't really specify.

Lastly, the printer DOES boot and the only issue I'm having with the printer is it keeps saying the red ink cartridge is faulty even though I've replaced it twice with new HP inks. I've checked the right ink supply station with a multimeter and verified all the wiring is good back to the printmech board. I'm thinking the faulty ink error might be because some of the parts in the printer don't match up.

Any advice in helping unravel this basket case is hugely appreciated. The printer ALMOST works! I'm so close!

The printer 

[skuks]

like it's said in manual:

"When the part is described with a specific revision (Rev A, B, C or D), this indicates it is only
compatible with the revision shown. If there is no revision shown, this indicates it is compatible
with all revisions of the printer."

https://shared.swissparts.ch/Manuals/HP/Plotter/HP%20Designjet%20Z2100,%20Z3100%20and%20Z3200.pdf

and go to 209 page...

So replacing formatter - HDD must be replaced with one of same revision...