I may try that with my Scott LK-72A amp. Even though the power transformer is fused a little more protection right at the power tubes cannot hurt anything. I may try and add a neon lamp across each resistor so I will have some indication if a resistor burns up. I used the JJ 76591 once and one of the four tubes developed a short to the grid after only using them a week. If only the Groove Tubes 7591 were a little smaller in diameter and not quite as tall.