ISX cm871/w PTO, cant fast/high idle

[jbird]

I have a 2010 Freightliner Cascadia with a 2009 cm871 engine. I recently added a pto and positive displacement blower to blow barite to rigs here in southern Louisiana. To get blower at optimum
operating speed the truck needs to high/fast idle between 1000 and 1200 rpms, but my mechanic,
as well as two local freightliner dealerships don't know how to get truck to high/fast idle. I saw in a post somewhere on the net that the cm871 needs a optional switch directly wired to the ecm, but freightliner dealerships are have no clue. I am using a crude wood block under pedal method right now, and a switch would be easier and cleaner since footwell area is frequently very muddy around rig locations. Any help would be greatly appreciated