I got the info from the Penn Elcom website and it's hard to tell how much recess there is on the 1536 corner or if it's the same part on your KP301's. The drawing for the part really only shows outside dimensions. Have not contacted Penn Elcom. I just assume that they sell larger quantities and I need to find a dealer, like Parts Express, who carries them. Maybe Parts Express could special order a few. Haven't checked with them, either. Better yet, maybe there's a business opportunity here if I order a big quantity to sell to all the KP owners whose corners that have cracked and split. (Perhaps I'll corner the market! - da dum - I'm here all week, folks....) I've used lots of the 1539's from Parts Express on other cabinets, but this is the first pair of proper KP's that I've re-cornered. It's good to know that they will work, but if I find out anything on the others, I'll share it. I was just hoping that someone else had already been through this. One other thing I thought was funny - the only photo of a KP-301 on the Klipsch website is that of the KP-301 II and it has a corner missing in the photo! What's up with that? Was that the only photo they had? They couldn't find one more corner for the photo? Or at least take one off the rear and put it on the front for the photo for cryin' out loud!