I've got a couple of those cheapy tach/dwell meters that you get at the auto parts store.. Actron, Sunpro, whatever, that seemed to work OK back when I still used them.
My favorite though, but not cheap, is a Snap-On cylinder shorting tach that is kickass for finding weak cylinders. I need to make up some kind of adapter for it though to use it on this newer stuff.
The Sunpro I've got does 2 & 4 cycle, if you want it, PM me an addy and it's yours. Still got the manual with it and everystuff.