Research: Acg Slab Serial Numbers - Black 2 Line Reverse

This is a research project into the history of slabbing. I don't care if you like ACG or hate them - not the point and I don't want to see that fought out here again. If you care to share information, thanks, otherwise just move on.

I'm trying to establish the ranges of serial number for various slab versions from Condor101's book. So beyond what I list below, can any other reader supply other examples?


ACG14 - Black ink, reverse says "ACCUGRADE(R) / SINCE 1984" with the (R) (registered trademark sign) almost full height with the rest of the lettering, SINCE 1984 is uppercase and regular font (not italic).

Condor's book shows 155285
I have 155762


ACG16a - Black ink, reverse says "ACCUGRADE(R) / Since 1984" with the (R) about half the size of the E and the Since 1984 in italics and upper/lower case.

Condor's book shows 157286
I have 157974, 158057, 158071


Unlisted - like ACG14, except Since 1984 is mixed case italic (i.e. the obverse is ACG14 and the reverse is ACG16a.

I have ACG159039.

All of these interstack (there are versions of later slabs where the little stacking ridge is on the reverse and so they do not interstack)


Thanks in advance for all respectful replies!