Codes po300 and po1345 out my ears.anyone got information on this?

 

This site is specific to Third Generation F-Body vehicles (hence, the title). Very little about your truck is shared with 1982-92 Camaros and Firebirds, except the short block, and possibly the rear shock mounting bolts. You may find more specific information elsewhere, since there are numerous sites dedicated to C/K trucks, and some good general automotive sites around.