Hi, Tim. From what you have given, I think that you want 6 risers each 8-11/16" high to give you the required rise. Now what you have to figure is the distance out from the deck you want to go(run). Since you want the tread to be about 9", you can draw it out for 5 treads 8-11/16 or 9" nicely. But do draw it all out first and make sure that it is going to fit before you cut. (I don't do it either, but it sounds good.)
Set both of your gauges at 8-11/16" (or the one for the tread at 9')and mark the spaces out on the 2x12. Use the same angle for the bottom where it hits the ground and the top where it hits the rim joist. I think that I am telling you right so do measure and check before you cut.