Thermoquad idling issues

[1] Whistle at idle. Some carbs do it, nothing wrong or anything to worry about.
[2] T slot close to square & mixture screws 2 turns out? Turning the screws in should stall the engine. If not, the engine is getting fuel from somewhere other than the idle port + a small amount from the t slot.
[3] I have never drilled the primary side air bleeds on a TQ & do not advise it.
[4] The PCV may not be working with the low vac. I would disconnect & plug it; then re-adjust mixture.
[5] One thing that concerns me about these re-man carbs. Internal corrosion of the alum passages. A re-man TQ on another engine that I tune has a problem whereby one mixture screw has no effect: can screw it in to seat it or back it out 6 turns, nothing changes. I suspect corrosion may have blocked a passage.