So, maybe we should just back up a step and ask what the symptom is here.
If the radio won't transmit, the finals are not the only thing that can fail.
And if they ARE bad, the next question is how many other parts got clobbered by the overload current you sometimes get from a fried final transistor.
The problem with just replacing finals is that you don't know if they are bad.
And if other stuff is bad besides, replacing them alone won't fix it.
I call this the "sideswipe" problem. Sure this car is a wreck, but how many other cars did it bounce off of before it came to rest upside-down?
Do you have any tools to identify what has failed. A multimeter would be a good place to start. A wattmeter is pretty necessary.
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