New inner leaf openings against original wonk?

[Digmixfill]

I'm starting to look at putting blocks up above dpc and some of the openings i'm lining up with are anything but true vertically. Concave, convex and slanted are all in the mix.

How best to align the sides of new opening with the old? I've considered the widest point, the narrowest point and the distance between the average of each side so far.

 

Edited October 19, 2018 by Digmixfill

[nod]

If you make sure that the new openings are wider at all points than the original You fix your frames to the outside leaf and pack off the straps off the inside 

and plumb when plasterboarding 

[Digmixfill]

Having the opening wider and trued up with plasterboard make sense. ?

As i've got 9inch external leaf i'm hoping to attach to the external. I can decide which way to fix when offering the frames up.