Visit http://spookcentral.cjb.net/rgb_makingof.htm to download the complete* featurette of Slimer Won't Do That! The Making of The Real Ghostbusters (1990), 19:19 length, 251Mb, .avi video file. British-produced by Central Independent Television. Video: XVID 656x496 25.00fps 1640Kbps. Audio: MPEG Audio Layer 3 44100Hz mono 128Kbps.
*In progress, but has complete end credits.
The Making of The Real Ghostbusters features Dan Aykroyd, Harold Ramis and many more people involved with Ghostbusters and The RGB. A Frank Welker/Maurice LaMarche voice recording session is shown at 10:09, followed by an interview with Frank. I've posted a few audio files and screen shots below:
[Frank on Voice Acting, Part 1, 371 KB: frank-1.wav] [Frank on Acting, Part 2, 613 KB: frank-2.wav]
Many thanks go to Paul Rudoff for the screenshots and video of Frank's section of the featurette seen above.