If you use 1/2 of your 12ax7 as an input, 1/2 as a split load (cathodyne) inverter, then use the triode section of your 6qw8s as driver stages to add gain for the pentode section. This should give you the early breakup of the cathodyne, along with the added gain normaly found in a long tailed pair. If you want you can balance the driver stages to make them look like a long tailed pair, but instead of grounding one of the grids, you use both inputs as a differential amplifier feeding the pentode sections.