roughly how much does it cost to convert from an auto to 6 speed? and what are all the parts that i need?

 

Tranny, Bellhousing, Pedals, Hydraulics, shifter, clutch kit, Flywheel, crossmember (can't remember if the A4 and T56 were the same), wires and connectors.
$1500 for a used complete setup usually. Sell your A4 to offset the cost.

 

I paid 2,000 for all of the parts including a new SPEC 3+ and PRO 5.0, then figure another 500 for stuff like a tune and other random things.