Sorry guys ran into another question,

If you can see by the pics below (its the end of the hallway where the stairs start) i removed the carpet bullnose (it has a lip bottom and top to allow for tack strip next to stairs, so i had no choice) and then found that there are two joists #1 and #2, however #1 bows about 1/8" near the middle so i was thinking of using a router (resting on the subfloor) to even out that joist and then finish the small piece with 3/4" ply (original is 5/8"). However i got to thinking that this is a crucial sqeeuking point (for lack of better words) so i thought i would cut back the subfloor to the #3 joist and then fasten a 2 by 4 to it and that way extend the 3/4 subfloor piece another 5 or 6" thereby making it mor stable. U guys think that is necessary?

Also you see that the mdf riser sits below joist #1, i am leaving the mdf and adding 3/4 paint grade maple plywood to the riser (glue and nail). The maple riser will sit flush to the bottom side of the subfloor to add stability to this new piece of subfloor i am adding. Hope thats not too confusing.

went to get somew minwax today for the nosings. i have bruce kennendale prestige plank 3/4" natural maple, you guys think a couple coats of poly will match? never done any coating before conmpletely new to it. Heard i should use water based? just plain confused i guess , thanks for any help.

sorry forgot to say that my floor is prefinished, checked the website says they used some dura-luster? well i think its low gloss but not sure. geez so confused

If you use an oil based it will amber. If the Maple flooring you have has a water based finish your unfinished will not match the color of the floor. I would do a test piece to compare before finishing all of the pieces.

thanks kls any suggestions on the subfloot piece, or was i too confusing with my lack of proper words.