I'm going to convert our AC over to Red Tek after the shop finishes some needed repairs (popped hose, new expansion valve, etc.). I'll start with a vacuum in the system. However that happens, oil needs to go back in. I supplied the Van Cafe o-ring set which includes PAG oil (OK for Red Tek). The question is how much oil are people using with Red Tek? That is, are you using the recommended amount or...?