Floor Boards to High

[musszzy]

Hi
I am removing all the floorboards in my hallway and will be fitting chipboard that is not quite as thick as the original Floorboards. This is fine as i intend to lay a floating floor over this. The problem i have is there used to be a door which has now been bricked up however this doorway had the floorboards running in a continuous length through. The result would be approximately 5 boards coming out from the wall by about 6 inches at a higher lever.
The doorway has been bricked up to the lintel for some strange reason personally i would have just used studded this out and boarded as it is an internal wall.
My options are:
Remove bricks and stud (lots of work)
Is there a way of reducing the thickness of the boards easily... if i plane it then i would have to plane across the wood as the wall would restrict my planer.
Ideally is there such a thing as a planer that has a blade on or near the front ?

 

[footprints]

I would use thicker board or shim / pack the boards to the right hight myself.
Belt sander might do the job but I would keep the same hight given the choice.

 

[musszzy]

Ii am going to put a floating laminate on top. The chipboard would lower the floor by a few mm to offset the floating floor as i did not want to raise the floor to much.

 

[Gerrydelasel]

When you've removed the hall floorboards, can't you just saw through the ones that are peeking out under the bricked up doorway?

 

[musszzy]

Sorry did not explain that bit. They need to stay on a joist which is where I will be cutting them which leaves them protruding 6inches in to Hall. As I said someone has bricked up the doorway so the floorboards are supporting the brick. I think it will be a problem if nothing supports boards