Originally Posted by 1978SeaRider
Engine tab looks fine too
In what way does it look fine? You need to set it by trial and error.
Knowing that the single engine will list the boat to the left and not wanting to move the engine you've only got a few options left to improve it.
One of them is the engine trim tab: When you steer the boat left it leans to the left so you need to adjust the trim tab so that the tab forces cause you to steer a little to the right so that the boat then tries to lean to the right. It's a balancing act and you may not be able to completely neutralise the forces but since you've got transom trim tabs I'd expect you can get it within acceptable range.
Put the fat people to the starboard side...
Edit: Just a thought, if your transom tabs are Bennett, the switch is marked with reference to the bow not to the stern so if you press the left switch down you are actually lowering the right tab. Other tab manufacturers may be similar, I've no experience of others.