Impressive site. The guy put ALOT of work into that....as another amateur photographer the work had to take a long time just for the photos alone. Very detailed. I like that. I tried to do something similar, but I didn't do that well. His website time was long too.
On the other hand, as a "Shade Tree" there is one problem with his mechanic work. He used WAY TOO MUCH silicone rubber (about picture 24 of 41). If that much squished out on the outside it also was on the inside. And in there it is free to get in the bearings and the oil passages. Not good at all. The amount needed to seal the head cover is a THIN THIN coat with all excess wiped off the edges. The headcover is machined flat and doesn't need much. Trust me, I've done this job a few times.
He forgot one pic. I just put it on my site and now I'll paste it here (small I hope). This is what you need for the job...print out the bolt pattern, tape it to a box and punch holes for all the bolts. "The Plug", sealer, o-rings, and seals are shown.