Wrong engine

I don't know how y'all still in business. I bought an engine ,put in my car and didn't start .toke it back, and the service was worse than before. They made me drive with my engine from selby to Denver to meet with another rude person that told me I won't get my refund. Reason being import engines are not 100% the same with SA engines, in the process of fitting the engine I had to replace same parts with my own engine parts for it to perfectly fit ,only to find out the engine was of a different model car .just like that my gurrenty is voided. Now am sitting with an engine I can't use