Appliance repair
 

I have a GE microwave oven that quit working today.
M# JVM1870SF02 S# AH908172B
I am a HVAC service tech.
I walked through the trouble shooting ladder.
It looks like the magnitron assembly is bad.
5.8 amps going into the HVT all other readings are close to what the book says but no power from the magnetron.
The Magnetron has a ten year warranty but the labor to install it is not. I can buy the part from GE on their website for $139.00 plus tax.
If I take this thing to be repaired the labor will be more than the part cost.
Is their any way to test the magnetron to be sure it is bad?
Is their any way to get the part under warranty without paying for labor?