black pearls of wisdom !

I see what you did there ......
Mate these heads bolt straight up no problem. Basically the same head, the 83/84 head had some mods not found on the B2 head but it will bolt onto a B2 motor no worries. Cams are slightly lumpier in a ZX head compared to B2 cams, but you can bolt some B2 cams into a ZX head. This is probably a backward step, as the ZX head runs a static c/r of 10.25:1 and will get better benefit from the ZX cams rather than the B2 cams.
The ZX heads go really quickly because these are the best air-cooled 2V heads for any of the old 1100's. You can also fit these to the earlier Z9/Z1000 motors with some easy mods.