My '93 extended cab has been modified with Bilstein HD shocks on all 4 corners. Major improvement. Also added a 23mm rear sway bar from a junkyard Bronco II and replaced front and rear bar bushings with Energy Suspension poly bushings. Handling is now fun again. I don't expect it'll keep up...
Easiest way to add a tach to your Ranger would be to get an instrument cluster from a junkyard Ranger of the same vintage with the full instrumentation. Should be just plug and play. '93s and '94s seem to be somewhat proprietary. Clusters from other years won't quite match up in all...