Hello, I have a 1999 S10 Blazer with 67,000 miles. My heater core began to leak Dexcool into the evaporator box. I flushed it out and by-passed it with a union (Heater core is now unattached from the coolant loop). I took the dash all of the way out of the vehicle to replace the heater core and noticed I needed to remove the heater/evaporator box in order to gain access to the heater core. My question is Instead of taking the evaporator box all of the way out, can I get to the core by cutting the plastic evaporator box, change the core, and plastic weld the evaporator box back together? This would be a major time saver for me if possible.