Sorry. I went through that scene on my copy of Ghostbusters 6 times - just couldnt make it out. (admittedly, it was a tape, not a DVD) someone else may have better luck. Sounds like a cool project tho'- I have the Polar Lights ECTO-1 in the stash (I'll get to it some day)
PS: I posted your question in the builder's forum at ECTO1.com (the definative site for ECTO1 geeks) I'll let you know if anything turns up.
"Growing old is inevitable; growing up is optional"
" A hobby should pass the time - not fill it" -Norman Bates