The generic locations should be the same as on my six. The "throttle postion switch" is on the end of the throttle valve shaft, which is under the fuel distributor on my six. It is an enclosed switch with a built in pigtail with a connector on the top of the manifold, which can be disconnected, and the switch can be tested for function.
I can't recall if the switch is closed of open at the idle position, but if you connect and ohm meter the resistance should go from zero to infinity, or vice versa when the throttle is excercised from idle to open. If you don't get a consistent jump in the meter as you manually excercise the throttle linkage, it is sticky. I was able to douse mine with mineral spirits, then WD-40, and it started working consistently and my high idle went away.
There is also a "microswitch" on the linkage, and it should also be tested for proper function in a similar manner.