I think with what you are dealing with, should be considered in what you are trying to actually accomplish.
If you are trying to please people of it being HC/PC, then you will need to thin it down.
However, I doubt that 95% of the people that will actually see it will ever know the dif. The everyday person seeing the rifle either way is not going to know it is thick or thin...... they just see a longrifle.
People on here will see it, as they are looking for correct reproductions & want to keep things as historically correct as possible. And one being too thick anyplace will be noticed on here. Nothing wrong with that, that is what keeps Lancasters Lancasters, and Lehighs Lehighs..... etc.
I am not saying you should or should not go on with it as is, I am saying you must decide How Correct you want it to be, and proceed from there.
Keith Lisle
PS: Most the guys I have seen cutting Precarves, are just running machines, not building rifles. They cut the patterns the vender supplies them, and wear the patterns out from then on. Some of them don't have a clue what is correct, incorrect, worn, or whatever. They are paid to cut the pattern.