93 Nissan Pickup 5spd w/ 76000 miles, i go to start and the starter sounds like its spinning freely and the engine wont crank...i still have my guages and lights, and the fuel pumps coming on, but it wont crank

From your description, you probably have a few broken teeth on your flywheel. A way to confirm this is to place the transmission in gear, release the brake and rock the truck back and forth a Little. Take it back out of gear and try it again. If the starter engages, it has confirmed my suspicion. This is the most common finding for the symptom you have described. I have rarely run across a started drive gear failure on a Nissan product, bar none, since 1968 until now! IF, however the test I have given you has not resolved the problem, this means that the solenoid has not kicked the starter drive gear out far enough, the drive gear it self has failed or the starter is loose causing the drive gear to be too far from the flywheel teeth to contact. The latter is a 1 a 100,000 shot!
You question has been answered by mybunkey, an old school Nissan master tech,. I hope my answer has proven to be useful.