Okay I know it's probably not even worth the money and effort but how much would it cost to convert my auto RS into a manual?

 

Well first off you need a tranny, master cylinder, slave cylinder, pedal assembly, shifter cables, tranny mount(s), axles, shifter assembly, umm i think that might be it. Labor will depend on if your doing it or a shop. Anyone else what to add to this?

 

and a flywheel / clutch /starter

 

And maybe most important of all, you might need an engine.

Years ago, for one of my customers, on another brand, I converted a car from a stick to an automatic transmission and it went well. Well, one day, a friend of the first customer asked me to convert his car of the same brand and model from a auto to a manual. It looked like it was going to be easy (the body had all the mounting points for a clutch pedal) until I got everything down and found out that there was no hole drilled in the rear of the crankshaft for the pilot bushing.

You had better check with the parts department to make sure that the crank for the stick version of your vehicle (make, year and model) is the same as the crank for the automatic. They might be different and don't thing you are going to drill a hole lying on the ground with a hand drill. Metal is too hard and it takes too much precision.

 

Yes the cranks are the same, the swap has been done in exileracing did on in an avenger which also shears the 420a. Search on this topic and 1 million posts will come up saying no... also you will need a new ecu.