Superior Instruments TV-11 Tube Tester - burnt resistors

[footlooseman]

I recently bought a Superior Instruments TV-11 Tube Tester. The line adjust control was not working correctly but was working after replacing two capacitors and some resistors that had drifted. There was one that I left in and it was a 330 OHMS. The unit seemed to work well but after doing some testing I saw smoke and thought that the selenium rectifier went bad, but it was this resistor. There was no listing for wattage so I replaced it with a new 1/2 a watt resistor.

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After testing some tubes from my Zenith and Setchell-Carlson TVs, I saw a spark for the unit and unplugged it. Took it outside and found the new resistor bad too.
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Went back to my booklet and found a part replacement list and it listed a 350 OHM 3 Watt resistor. I'm guessing it an oversight on my part and still kind unaccustomed to some of the vintage parts.
What do you guys think made the original resistor fail? Did I over look some other parts? Should I go with a higher wattage resistor such as a 5 Watt?
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