[Glenn Roberts]

I'm going to start off by apologizing if this is a nooby question. All 3 of the bias resistors are blown on this set. The 150k resistor is larger than the 10 and 15, does it need to be a 1 watt or larger? There isn't a notation on the parts breakdown or the schematic. What would cause all three to blow? I found the 80 tube and both of the XXL's weak. I'm replacing all the crumbling wires but the only burn spot on the chassis is where these were located. Any help would be greatly appreciated, I want to make sure it doesn't happen again when I give it a test run. I have a nightmare that it caught on fire the first time I tried it (even with a variac)...
Thanks
Glenn