A Plan or Not to Level the Floor?

A Plan or Not to Level the Floor?
(Climbing the learning curve on fixing old houses)

1) Have a rim joist that sits about 1 inch above the other joists which are 16 inches O.C.
This causes a rapid drop in the floor from the wall and then it is quite level.
Appears originally built this way.

Rather than tearing up the entire subfloor , T&G old growth pine, I’m thinking of mounting a sister joist
on the Rim Joist for the entire length needed (8 feet). Then cut the T&G old floor at the joist
next to the Rim Joist and nailing in a piece of “3/ 4” plywood which would span the area from the
Sister Joist to the Joist next to the Rim Joist. OK or got a better idea?

2) Rim joist is “2 x 10” so thought a “2 x 8” or rippled “2 x 10” so that the bottom of sister levels with
the original Rim joist as a sister?

3) Planned to use 8d nails in an “M” pattern, and pre-drill to stop any splitting as the rim joist is quite old.?
Alternatively would screws – maybe DeckMate – or Ceramic Coated – or 3/8 lag bolts be better?

4) Everyone seems to be an advocate of gluing plywood to the tops of joists to stop any squeaking. Anyone have any experience trying to remove a glued plywood floor and what if any destruction of the joist it was glued to after removal (i.e. is an new joist then required)?

Any input appreciated.

Not sure I have the picture in my head. If I have it right, the floor joists are crowned down except the one at the wall and you want to leave like that. What you have described will work fine. Three 3" nails 16" on center is all you need for laminating joists.
When removing glued plywood from floor joists, some plywood stays there that will have to be chiseled off. Never seen dammge to joists but if did have some you could just laminate a 2x4 or something to it.

Thanks nealtw. Nice to have your input.

David