Hi Guys, another Newb here!

A couple years ago I purchased a rebuilt "ready to go" '89 550 I made the massive mistake of not meeting for a test ride when purchasing it and have had nothing but let downs ever since. The ski would run great on the stand then surge when in the water and under a load. I took it to a home mechanic and hundreds later launched it and had the exact same problem. Then I took it to a shop where I was told the head doesn't match the cylinders and they rebuild the motor put on a new head rebuilt the carbs and who knows what else. Again hundreds later I took it back to the bay and it ran fine for about 5 minutes before starting to do the exact same thing. I tried messing with the carb and only made things worse. I flushed it, put it back in the garage and have tried to avoid eye contact since then. I live in San Diego and I need a mechanic with a tank or who is willing to take it to the bay and get it dialed. Go ahead and make fun of me for wasting so much money on a old 550 and whatever else, I know I deserve it. Does anyone in the San Diego area know of a good, honest, reliable jet ski mechanic who is qualified and willing to see this to completion even if that means test riding and dialing it in at the bay?