1968 Z on BAt

[RamAirBirds]

A quick question regarding the VIN stamps on these 68 Chevrolet Blocks.
In reviewing what is a REAL stamping at start of this thread. On the "M" is the middle of the "M" supposed to be all the way to the bottom of the character or have we seen some where the middle only travels 1/2 or slightly more down as in the car sold on BAT...Reason I ask is I have a 68 Z all original that had the block decked and re-stamped WAY WAY back in the day...The party had access to original GM stamps locally (Detroit)...This was normal many many years ago...My characters on the pad look exactly as the BAT car does...I mean exactly...every character...I was surprised and happy to see that...I am just trying to clarify as when I sell/market my LOS built Z it will be with full disclosure as to this fact...It looks perfect but just curious about the "M"....Have others been seen with the "M" that does NOT have the middle travel to bottom as in the BAT car? Does a LOS built car factor into this at all?
Also.....I posted here before but my car also has a correct Cowl Plenum AC that was added so so long ago...but am unable to find a BOOT for the system...ANY ideas? or any material that anybody knows of that would be somewhat correct, so as to make one? Really need help here...The car would greatly appreciate it as well...No Heartbeat does not have the repro one any longer...Not even sure how correct that one was.....Thoughts.....Thank you SCR....Just a Pontiac Guy looking to the experts on Z's...