ZLX question

[Schonyenko2]

I went and found my old copy of that book. Mine may have been an older edition as there was no mention of the ZL-X. But in the process of looking for it, I came across my old Nickey, and Berger catalog, and they both list it. Berger:1/2 engine assy/short blk, 0699 427/430 ZL-X 12.0 to 1 open chamber. 1/4 engine assy: fitted blk 8656 427/430 ZL-X 12.0 to 1 open chamber.
Nickey's reads: 9960 427/450 12 1/2 floating wrist pin, 4 bolt solid cam ZL-X L88 open chamber. I think they may have the part# backwards.
So it basickly is, with 026 open chamber heads, a cast iron ZL1.
It appears this was kinda the transition/ evolution to the LS7 454 crate motor.