Shorten by HOW MUCH (or more help please on s2172)

I knew when I made up the skirt that I alterations would also be needed on the coat.
On the skirt I had to shorten it by 10inches, to keep the proportions correct I did 1inch off the yoke, 4inches off the main skirt body and 4inches off the pleated hem.

Now then the coat is so long 54 inches and I am so damn short that I have to shorten it to 41, even then this will be as long on me as it is in the pattern picture.

So my question is how do I shorten this by such a huge amount.
Do I,

• alter the paper pattern first and run the risk of the curved edges not matching up.
• make up one back half and front section in calico, then shorten it, take it apart and use that as my pattern.
• I can't think of any other methods.

I also think I may need to forgo the pocket as that may be too low down. I don't mind this.

As on my last post about this outfit, again I greatly appreceate all answers from you lovely sewing bloggers out there,
Many thanks in advance from a very mystifed Sew Vala. xx