360 is still running hot

I would take the thermostat out all together. Don't really need it in there if only driving in the warmer months. And you are also blocking half of your radiator. You bought a 3 row and electric fans but you are only cooling where the fans are. Cut some big holes in the spots where there are no fans. You are blocking air flow everywhere except where the fans are. Its there- use it. I have a stock 360 with an old beat up 2 row radiator and it never over heats. I don't even have a shroud on it. Also- is your radiator coolant mixed 50/50? Another thing is-take your upper rad hose and unhook at rad side and lift higher than block and rad. Use a radiator pressure checker and "push" Rad coolant to try and make sure of n air pockets in head. May even be able to unhook heater core hoses and lift those higher than engine and rad.