I don't see a reason why it would be unsafe to remove Q21/Q22 and measure the voltages at the bases.
If the pot is aged and worn out, the wiper may loose connection during adjustment, causing the circuit to be biased too high.
You should be careful adjusting the bias setting on the pot.If you get it wrong, you will saturate the drivers Q17/Q20 and then rapidly the output stage Q212/Q22.Before you even notice then, the weakest end of the pairs will burn out in a rapid thermal run-away.
I suspect that you have a problem in the bias stage Q3/Q18
Also if capacitor C12 is a dried out electrolytic one, it will no longer dampen rapid changes during adjustment.
Notice the diagram voltages written at Q8/Q19 emitters.These voltages should be spot on and replicated in the high end emitters Q1/Q16.
If these voltages are not spot on, you should investigate the differential amplifier Q2
have you done a basic check on the power supply ?
You can't just remove them in THIS amp. Then the whole amp has no DC feedback anymore.You could remove them, and temp use a ~100-220ohm resistor between B and E.
Just short the whole bias circuit. e.g with a jumper/solder blob over C12.That way you can rule out the bias circuit while fixing the amp.Without bias, the amp just has a lot of crossover distortion.
Did you use branded transistors. There seem to be a lot of "fakes" around.
Does the amp also blow without a load.
To set it up from scratch, you replaced the fuses with 100R 2W ,I think resistors.
I R to dumb to understand this advice I should swap the fuses in the circuit with resistors?
Are you sure this is ok??