Still bubbling out overflow after changing water pump, thermostat, radiator,hoses??

So it was doing this before replacing parts but after sitting for 20 years.

You see where I'm going here. Same problem with old parts as new parts, so most likely not new parts or radiator fill issue.

My bet is that after sitting for 20 years, it has an issue with head gasket or metal has been eaten away allowing compression pressure to enter the cooling system.