Guys, guys, guys... the best way to explain anything is to just show it. Here's something I put together quickly using Harmy's Despecialized 1.0 (yeah, yeah, I know, but I had to make room on my harddrive and I'm waiting for the Bluray) and the ISOmix set. So here, picture in picture are the 77 and 81 crawls.
https://mega.co.nz/#!uQ4zwKpa!Pu9SdzmNw-bZaUWN0OeDPTba6y9BP_gShQc9FM2X-Fw