And I need to order valves soon. Looking to pick up a set of used 6.1 valves. This is a budget build as much as I can make it. And the fact that the exhaust valves are the same size and sodium filled for heat dissipation is an added bonus. Intake are .0050 larger. Bigger but not enough to go crazy about. And since I was getting a valve job after the head work means it won't cost any more or very little to get better valves. Only concern is that I have read the 6.1 valves have a slightly longer stem height. Info I can't find if it's above or below the lock rings. Either way I can fix it. If the extra height is above the lock groves, mill down the height. Or change push rod length to a slightly shorter set. If extra height is below lock groves, mill the height slightly again. But add that much back as a spring seat spacer. This is the only way I can think to keep the proper geometry in the valve train and keep proper spring seat pressure. Too much length under the retainer groves, less spring pressure and rocker geometry change, to much above the lock and rocker geometry changes. If the rocker geometry changes too much there will be increased wear and stress on the rocker arm with a possibility of breaking. Worst case scenario is the extra pressure on the valves cause them not to seat properly. Low/no compression. Either way, no go. If the rocker assembly was adjustable, then there wouldn't be near the worry. But their not. So this is how I have to do it. This might be a budget build/swap, but I'm going to make it right.