Sounds like you've got a multitude of problems.

I would suggest either an engine swap or a tear down and rebuild. You might look at doing it yourself with the help of a mechanic on the side. Since you work at a parts store, you should know who you'd like to help you.

Another option would be to look at a new engine, maybe from Jasper or something else with a REAL warranty.

Sounds like you've got problems in the head and short block.