On July 15/69 L89 aluminum cylinder heads were cancelled for use with LS6 for 1970 production. On Dec. 1/69 a memo statesthat L/78 was to be available with Z/27 until LS6 becomes available. On March 6/70 memo states LS6 will be available with M/22 or M/40 only as RPO Z/15, though availability not determined as of yet. And so the rumours start!!!!