Ok loose calling station with a high vpip you need to be widening your value 3bets to add hands like AJs,KQs,99 etc....Reason there calling a ton and your range crushes there and there unlikely to fold.Hence it would be terrible to 3bet light.
Ok vs a TAG at 6 max lets say villain is 18\16.If they open a pot there going to be raising.Lets say villain is in the CO,hero is on the BTN(BTW most tags know they shouldn't be calling a 3bet oop).Ok lets look at villains opening range from the CO.Look at his steal BB stat also this will help define his range.His steal % is 30%,So his opening range is leaned more towards ~30% rather than 16%.Lets put that in stove.
55+,A2s+,K5s+,Q7s+,J8s+,T8s+,98s,A7o+,A5o,K9o+,Q9o+,J9o+
We have A4o on the BTN.Since we hold a A we cut his combo's to nut hands AA,AK etc.Since villain seems to have a understanding of position,he knows it's not good to call oop in 3bet pots,there for it's a good spot to 3bet this TAG
Make sence?