Mr T - I was just about to dig out some photos to show my whole Frankenstein approach.
But, given your build skills, I see no problem with replacing the original sills with some box section.
As you know, my car can be described as 'solid'.
I've got your number, so will ping you a text in the morning.
I'm still not 100% sure how my day is supposed to go, but hope to see you on Friday.
Cheers, Paul.