Engine starts. Very rough idle and harsh popping.

Recent History (Approximately three months Ago): Local Mechanic changed oil, replaced distributor, rotor, plug wires. I replaced plugs a few weeks prior. Engine Light on at this time, however Mechanic forgot to read codes. I generally only drive very local and truck seemed to run fine, so I put it on the back burner. After a month or so, at 40-45 mph a miss developed. Continued driving. Approximately another month later, a miss began at 60-65 mph. Back to mechanic. Code called for new computer. While waiting for computer, continued to drive local short distances only. Several days later, the truck will start, but idles and runs very very rough and pops (very harsh pop) when running. Will not stay running while attempting to drive. Truck sat until computer arrived. Installed computer. Engine light immediately gone, but no noticeable difference in performance. Removed all plugs, fouled. Cleaned and verified gap (.030). Plugs visually fine to reinstall, but no resistance test performed. Reinstalled plugs. No noticeable difference in engine performance. Throttle body is dirty (have not cleaned yet). No codes have been produced during this period, at least no engine light is showing. Prior to above issue there was a noticeable hiss noticed especially when cold but harder to hear when warm or highway speeds? Possibly air conditioner?
Looking for Help. I am tired of walking. Thanks in advance. P.S. I have a short video with audio of issue while running available.