I used this article to do an AWB Coronet when the magazine was new. I had the advantage of having a spare body (first one was warped, AMT sent me a new one) so I didn't need the filler strips. Instead I measured and cut both bodies using the wheel openings from the scrap body (cut farther back) on the good body (cut farther forward). It turned out great, needed no filler, just a skim coat. Sure wish I still had it!
The Z-11 was just a larger version of the 409 (not all aluminum) with better flowing heads. The all aluminum 427 was a one year option in 1969. It was an aluminum version of the L-88 engine and was called the ZL-1.