It's just a straight question on the best placement on my site. That should go to .com, correct?
There's actually a few articles on .org regarding adsense placement - https://vborg.vbsupport.ru/showthread.php?t=107965 is one of my favorites - it was written for vB 3.x series - but I'm sure similar (if not exact) placements on a vB 4.x board would work well for you.