This would probably be a good time to add some info regarding glitch resistors. It's not enough to just properly size the wattage and ohm value here. You have to go one step farther and consider what is going to happen to that resistor if you ever have to depend on it working during a tube arc.
For all practical purposes, an arc is a short between the two points the arc is occurring at. That arc is looking for ground and when it finds it, guess how many volts it's going to try and drop across that glitch resistor for a fraction of a second? How about ALL of the plate volts! While you'll never be able to practically size the wattage of the resistor to handle this, that is not the goal.
The goal is that the resistor has to be long enough to sustain that voltage spike without arcing from end to end. Remember, an arc is a short. So, if the resistor cannot handle that brief voltage spike, it will arc over and turn your carefully placed 50 ohm glitch protection, into a short right at moment you need it most.
While not the most technical method, I like to see about 2 inches of resistor, per 1,000 volts of B+. Less than this and you run the risk of adjacent windings on the resistor, wanting to arc. Once this starts, it instantly flashes across the entire length of the resistor. Actual high voltage resistors rated for glitch use, are long, expensive "Glow Bar" types. Feel free to circumvent that expense in most cases, by stringing the appropriate value wire wound resistors in series to reach the needed length and breakdown voltage.
