I began investigation of the first of the complete list of HVX Mods (Hoover Mods) I intend to implement on my engine. The camshaft bearing shown at the bottom of this picture will be drilled out to match the bearing in the middle for reasons given on Bob Hoover's blog. Note that this link is just one of several articles he has written about the subject. In later articles he also details relocation of the oil temperature sensor, adding valve stem seals, and installing a pre-oiler, among other general "blueprinting" and engine assembly tips. https://bobhooversblog.blogspot.com/2007/05/hvx-mods.html https://bobhooversblog.blogspot.com/2007/06/hvx-mods-again.html Here's a video of the camshaft procedure and a few of the others. It features a great cutaway engine to help explain things: https://youtu.be/ubwhsLNM1wU