Ford Ranger 3.0 leaking freeze plug, let’s kinda fix it..

This ranger came in with the heater not working and a coolant leak, the customer stated that the heater hasn’t worked for a couple years and it’s just recently started leaking coolant, I had to dig fairly deep to find the leak and I thought flushing the rusty crusty old coolant out of the system and flushing a bunch through the heater core I thought we would have been able to save the heater core.. but I was wrong and the customer declined the heater core replacement at this time.