Several years ago, I bought a left-handed flintlock GPR .54-caliber whose condition makes your rifle look good. To make a long story less long, I called Lyman. They had me return the rifle to them at their expense for repair or replacement as needed.
I requested, were the rifle unrepairable, to have it replaced with a left-handed percussion cap lock .54-caliber GPR. And this is what I received by return.
Design and quality control were completely different, metamorphosing from eye sore to a nice unadorned Plains rifle. The only problem was the trigger adjustment screws were so short that they adjust nothing. I queried the forum and discovered this problem is normal for GPR, and the fix for it is to buy a longer screw.
In the intervening years, the rifle has remained in the safe as my interest has moved toward bigger bores and double barreled rifles.
In summary: Lyman shipped a poor product. Lyman made things right without a murmur.
Hope this helps.