LS-7 #990 head

[COPO_Anders]

When you mentioned the #188 head I became confused. I´ll explain why:
I have a brand new 1989 crate LS-6 engine. At least that´s what I think it is.
It´s got a #14015445 4-bolt main block with forged crank and 7/16" dimple rods. The dome on the #3999295 pistons seems to be to small mabye for an LS-6 engine. The HEADS are #14096188 castings, with is a rectangular port open chamber head. It has 3/8" guideplates and of course 3/8" pushrods. This engine has also the LS-6 cam in it. I have always considered it to be a -71 version LS-6, that is with lower compression than the -70 LS-6. It had never been started when I took it apart to inspect it. The engine is stamped T05179XF. It has the same trap-door oilpan as the new ZL-1 crate engines.

1.Is there a #39XX188 head as well as the later #14096188 head ?

2. In which applications was the #3999295 piston used ?

Anders