My 95 Honda Civic has been running great since I replaced the head gaskets and intake gaskets, but the Oil Light came on and will not go away. I checked the oil and it is fine. Could I have a bad oil pressure sending unit? Or a bad oil pump? I keep all services and maintenance up to date but I have ran out of ideas.

Remove oil pressure sending unit and check oil pressure with a gauge.
Based on results, clean connections to sending unit and reinstall. If problem doesn't go away, install a new sending unit.