After talking to Tubular Joe for a few minutes, he explained how to rewire the input tubes to use 12AX7's rather than 6AX7's.
He explained that pins 4 and 5 on the 12AX7's are two 6.3v paths and pin 9 is the other end of said path. If you want to wire the tubes in this perticular way, you must run the tubes in parallel instead of the configuration that Bob has us running the heater wires for the 6AX7's.
Here is a photo of two different paths for the two different tubes:
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