Hydraulic roller lifter to solid conversion

It would definitely require a lathe and some machining skill to make it work. I would also be concerned about the roller needles, too. The tolerances are really good with the factory rollers, but I'm not too sure if the needles are hardened to level needed for monstrous valve spring pressures and valve lash. Not that I haven't thought about doing this, too. I have a few sets but haven't investigated them to great detail yet, do the lifters provide pressurized lubricant to the rollers? I would definitely look into modifying them to do so and use high zinc oil and/or additives.