are you building these stairs up from "naked" stringers or is this a "skin" being applied.
Normal stair construction begins at the bottom...with a tread then a riser is set on that then the next tread up is installed...it is a overlapping type of method similar to shingles on a roof.
Paint first, then stain. Then you can touch up the paint once done.
after then touch up
these stairs will be on naked stringers. now they have (2) tempoary 2x4's for each tread, which will be removed. they have no risers at this time.
Thanks for the answers, but I'm still hoping for more ideas.
sider stringers should go in first...then work you way up from the bottom Alternating risers and treads. You can "pre-stain" + varnish (poly) the treads ahead of time to eliminate some of the stain "bleed through" that often happens when taping off the white.
Thanks for all the answers -- problem solved