Hello, Let me preface this post by saying that this is my first ever post in a forum, so if I'm doing something wrong, let me know. This thread is a follow-along of the build for my 1994 Explorer XLT 4.0 OHV. I just figured that other 1st gen enthusiast, like myself, would enjoy seeing my unique approach to building my 4.0 to be an extremely capable daily driver. As for the truck, I purchased it in Seattle, WA for $1000 with 150k miles on it. At 200k I managed to blow the head gasket while playing in the TN ice storms... That's an excuse to upgrade! (or just rebuild, as far as my wife is concerned ) I bought a second engine from a buddy, and away I go! (First post, so I'm testing this out with a picture) "No officer, I didn't see anyone doing donuts in the addition..." OK! On to the story! First thing after the tare-down is to get what I need. And what I cant get I must make! I ordered a .020 over rebuild kit from EngineTech. Good price, but later, I found, some of the items in the kit needed to be replaced with higher quality ones. In tearing down the old engine, I found some interesting things that I wasn't aware of. It appears that the push rods are solid and the rockers tips are very poorly lubed from whatever happens to splash on them. This engine having 280,000 miles on it, the rockers were near non-existent and the push rods looked like spears. Because I'm looking for every excuse to upgrade, I went with a set of Harland Sharp roller rockers with the Morana racing adjustable rocker setup. These rockers come with a 1.8:1 ratio as opposed to the 1.5:1 of the factory rockers. This is all fine and dandy, but I had already decided to order the 422 cam from Comp Cams and with the profile of that cam, I would end up with .601" lift at the valve. Performance-wise, no problem.... Parts-wise, PROBLEM. I called comp cams and they were unable to provide me with anything that would work, along with Pac Springs, so I did some research and found that behive springs for a for modular engine could work as long as I modified the heads and valve retainers. Once I got the springs in, I took some measurements and determined that in order to minimize the machine work, the springs would be best installed 'upside-down' from the traditional installation. I reground all of the valves and put a nice 3 angle valve-job in the head and measured my valve spring height. I determined that by machining the heads approximately .0150" lower in the spring pocket while keeping the same diameter for the guide OD I would have enough spring pressure and travel. Next, I took the spring retainers and cut the OD of the spring seat smaller to fit the other side of the beehive spring. I used an endmill with a .0100" radius to help reduce the chance of stress fractures. Next, I test assembled the heads to check spring heights and travel. Everything fit perfectly, but in order to compensate for the height of the valve stem seals, I will need to cut the valve guides down a little.