I have a large Stanley and I am in the final stages of my first frame and panel door. My shoulders are looking pretty good but I have a very slight error n a few of my knife walls because I was using a utility knife and it tends to cut at an angle. After working my way around the rails it was a smidge off and I knew it would show. It is still less than the width of a playing card but I am doing this to learn how to build fine furniture. I am now ready to attempt to lower the high side in an attempt to get a good (perfect) seat on all sides. I hope that I won't cause more problems than I solve. Step one is to use a backer board because I screwed that up on my last use. For the tenons after using a router plane they are pretty true so I leave my mortise slightly tight and as I start fitting I check the the board for plumb and use a chisel to pare the mortice walls to adjust as I slide in. This is possibly the most over built basement/crawl space door ever made.