No, the Olds bore center-to-center is not the same as the Inline 6 bore centers, but it can and has worked in some apps as I mentioned previously, but its not going to work 100% of the time. And whether your instance is one of those cases, its hard to say because it is dependent on other variables, such as the cams base circle, and how the oil groove in the lifter body aligns with the oil galley in the block, and several other crucial items. But again, it goes back to someone trying to make something work in an application it wasn't designed for originally, and no lifter is going to work in the 250 or 292 100% except one that was intended or designed for it be used that way. I know of someone that has successfully used hydraulic roller lifters from a Iron Duke in several 250 and 292 engines, and that is where you should turn your attention.
