Thanks for that, telwood.
I spoke to a few rental service departments and all they could find was the operator's manual for the TEREX TA64. Genie said they didn't even have a record of a TEREX TA64 (Only a TA30). One guy who has been working on lifts for a long time offered to bring in some old paper documents he had kicking around. He didn't have what I needed but after chatting a bit and looking at pictures he said it must have been a Marklift model due to the axel type and the use of "OEM Controls" multiplexers.
Armed with that info I dod more Googling and finally figured out that this lift was originally a "Marklift CH64KB"
Here's a link to the Operator Manual from Genie's site:
http://manuals.gogenielift.com/Operators/English/TerexAerials/Marklift/17317.pdf
Unfortunately, Genie also doesn't have the service manual on there. The closest one is for the CH30KBN which doesn't have the jib and has a very different ariel control setup (same as the TEREX TA30). I'm gonna return the docs I borrowed from that service guy next week and while I'm there ask if they can see if there's anything in the computer under the Marklift model that doesn't show up on the website. If there is I'll update here.
Thanks for the help. To pay it forward I'll leave links to the "Terex Aerials" Service & Operators section of Genie's site since it can be tricky to find.
Terex Aerials includes TEREX, Marklift, & Simon brands...
Operators Manuals:
http://manuals.gogenielift.com/Operators/engomterexaerialsINDEX.htm
Parts & Service Manuals:
http://manuals.gogenielift.com/Parts And Service Manuals/1IndexTerexAerialsService.htm