I have used vasoline for rod and main bearings for years, but I would have a fear that it wouldn't lube the cylinder walls long enough and they would run dry and start squeeking. I really prefer to use a heavy weight oil that wouldn't run off quickly. You don't need anything to hold the rings in place, the compressor will do that. Don't forget to stagger the gaps and also check end gap closely. Too little and you may break a ring on heat expansion. As someone stated, vasoline is a big aid in assembling automatic trannys.
Truck Tinker
