Carb, LSN flush with the inner ring, HSN 4 turns out from the bottom.
You can do shock rebuilds by buying o-ring kits, new oil, possibly shafts and rod ends.
Take them apart, clean them out, replace all o-rings with new and refill with new clean oil. Messy job, but a good idea to do at least once a year if your a basher. Gets all the grit out and lets you inspect the shaft for wear. If the shaft is pretty worn, it's a good idea to replace them or the worn shaft will just eat at the new o-rings. Also a good idea to buy new shock ends as they get sloppy too.