No honest question is considered "Stupid" So ask away!
First the correct way to time your Car, Is get a Timing light, find the specs For your engine..(if SBC probably around 12 BTDC) locate and mark the timing mark on your Crank pulley, Disconnect and plug the vacuum advance line..Start and WARM the engine be sure the choke is open.
The Index plate on the timing cover should be incremented in about 2 degree incriments..losen the Distributer and advance or retard as required to get the lines to meet, on strobe with the timing light, then tighten down the distributer. Check and set your idle with Vacuum advance re-hooked up..should be idling around 950 for Auto, 750 for manual..
The highest Vacuum method works too but IMHO is not as accurate as the timing light especially for computer controlled vehicles. where timing is critical.
The "Glass-packs" since I have known them..(about 35 years) have always "Popped" on wind down...because of lack of restriction, are like an "Exhaust leak" Timing and carb adjustments may quiet down the effect when dead on adjustments are meet...but will never eliminate it...at least until you get a more expensive muffler, like a flowmaster..