I strongly suggest googling and reading up on how jackets are constructed before doing a conversion; I'm talking about the internal construction and interfacing.

Otherwise, you could have it converted by someone on the forum, and not worry about all the tinkering.
I do happen to be in the middle of converting a jacket and it has slit pockets that I have raised the flaps on, as well as, pleating in the back to form the flap rather than vents. It's an experimental conversion and design.