Done a lot of 3/4's in 12 and 20 over the last year.
Green Dot is for 20's
Red Dot is for 12's.
Red Dot burns dirty in my 12; they say the pressure to too low to burn completely.
Lot of talk on Shotgun World about 3/4 oz loads; apparently Extralite burns the cleanest for 12 ga 3/4 oz loads, but I haven't tried it.
Also, a copy of the load sheet necchi linked is in each bag of wads from CB.