i have my new tank and g12 ready to go,

whats the best way of taking the old one out with minimal spill?

do i need to buy new hardware once i loosen the metal crimp pieces holding the lines tight on the tank?

just pull the bottom hose on the coolant tank, then plug it with your thumb and pull the tank. unscrew everything first. this is how i do it on my 01 s4.

did you bleed the system??

i didnt. just left the lid off and let the car run for a while until all the bubbles were out. ECS sells a coolant flush kit you might want to look into.

Audi B5 S4 2.7T ECS News Universal Schwaben Coolant Evacuation Tool Kit - 003466SCH01 - Coolant Evacuation Tool Kit - ES#2712734