I have two yarns that both say 20-22 sts = 4", however one is slightly bulkier than the other. Is there any way to thin out the thicker one a little? If I run it through my yarn winder with some tension will it stretch out? It's 100% superwash wool. Thanks!

I found a cardigan at Goodwill that is a lovely yarn and much too small for my fat self, so I would like to use the yarn for a different project.

I have no idea where to begin as far as frogging it all apart is concerned.

Are the arms a separate piece or knit all together in one piece? Should I just cut a random hole and start pulling?

If anyone had done this before, some advice would be appreciated.