As I explained to you in the other thread, connecting your meter in series in a circuit to measure amps, results in very low voltages across the shunt (Ohm's law). So, connecting the meter to 600V or 1000V in series is no big deal, as long as the impedance in the circuit is much higher than the internal impedance of the shunt and fuse, usually about 0.01 Ohm each. Of course, the amps must remain below the breaker's rating (10A usually), or it will blow.
Now, if you put a transient of 8000V with an impedance of 2 Ohms on the A or mA range, all bets are off! It is in essence a short! 8000V and 40-50 amps across the fuse would cause havok on any meter. Very few meters will survive that, depending on the transient time.
The fuse may not even have time to blow, depending on the rise time, frying the traces upstream.
On the mA/uA range, the rectifier bridge and Zener diode would have to take the brunt of it, until the fuse blows.
I haven't seen the actual required procedure to test meters. I suspect that all that is required on the amp range, is to verify that in series in a circuit with a 600/1000V power supply with high impedance, there is not leakage or shorts in the meter. I don't see the point of blowing the fuses with anything above 10A/1A on the Amps ranges.
So, in essence, most meters are fine with 600/1000V on the amps range and are not limited at all by the voltage rating of the fuses, which is just an indication of their ability to contain the arc and energy, when a short occurs.