There are a set of plans for the XP-55 out there for free download on one of the sites, but I could not find it for you right now. I have them stored if you want them. I had them printed up and they look interesting. Not a complete set of plans for a model, but do leave a lot for the builders discretion. Much better than a 3-view drawing though. Has the ribs and fuse formers drawn nicely. It is on my list of things to build someday. I haven't seen the one in your article, but it looks like a neat build.

-Will