Fuel trims are in check but the car is still super rich

So just like the title says. Tuning in a LSA 408. The fuel trims are spot on but the exhaust fumes burn your eyes. I'm going to hook a wide band up to it to confirm. It is in a TBSS with new o2 sensors. If I confirm its rich what can I change to get the fuel trims back on track

Do you have any exhaust leaks or misfires? Do you have a full exhaust system?

You have verified you are in closed loop?

might need some eoit if the cam is letting some fuel out the exhaust valve, trims won't pick up on raw fuel as they only sense oxygen