Update - FiTech issued an RMA and I sent the entire TB back. Within one week they sent back a refurbed current version TB with the 4 + 2 connector. Incompatible with the V1 6 pin, but one email was all it took to get an undated harness. I bought the v1 in Sept 2015 and the replacement unit was No Charge. So while the v1 reliability is questionable, FiTech's customer service gets an A.
Took an afternoon to rewire the 4+2 connector, and the engine fired right up. During the downtime I purchased a new TB bracket from Lokar - specific to FiTech. The original Lokar bracket designed for Holley linkages flexed under WOT; the new one is stouter and has two connecting points. With the new TB and bracket, it feels like the engine picked up 50 hp. Runs the best it has in the 3 years since completing the resto.
Here's the p/n for the Lokar bracket. You'll notice the new spring on the bottom has a more compact range than the original.
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