The only reason I was curious about it is our 5.9 Mag has Hughes valve springs (1110's) and if it sits for a few days the stronger than stock springs collapse the stock lifters. they pump up right away after idling 30 sec or a min but it is irritating, it is a fairly mild Lunati cam with .485 advertised lift that is done by 5000/5500 RPM. I ran this car with a 273 for years so I am not intimidated by solids and just thought if there was an easy way to convert to solids I would, but we dont really need them for performance reasons.