1986 Camaro 2.8 5 Spd

Hey yall, I could use the brains of those smarter than me.

About two months ago my alternator seized and started burning the belt. Ever since I replaced the alternator I’ve had issues of intermittent stalling while at idle or in 1st, mostly when hot. I have replaced the fuel pump relay and let it idle for 45 mins yesterday and had no issue but this morning I started the car and went 20 feet before it shut off. The car always instantly fires back up but has a slightly higher idle after restarting. I’d like to fix the problem without throwing money at it.

Codes: 24, 32, 42, 54