hello, I recently bought a 50/50 and opened it up to check under the hood and the two heater resistors 101/102 are cooked badly. I removed the power tubes. I never tried it but the seller claimed it worked ok. Hopefully he's ok. This one has the carbon comp resistors which are pricey and hard to find compared to metal film. There's limited gut shots online but some newer ones I've seen show missing resistors in the 101/102 position. Were they moved? I'm trying to see if the newer ones had metal film resistors instead. They might be tougher than carbon comp and I wouldn't think tone should be a factor in the heater circuit. Not sure if upping them to 5 watt would be overkill. Mine has the deep mod but I'm not sure if it was factory done. The trace was cut next to the heater resistors and the yellow wire was soldered directly to a resistor. Not sure of the number. Seems like the newer version boards have revs. thanks for any help.