[Heathkit] Testing the SB-401's 6AV11

[jack m]

I have 4 spare NOS/NIB 6AV11 triple triodes for my SB-401's which test perfectly on my TT-1A tube tester.  All 3 triode sections of each tube are within 5% and well over the stated test minimums.
 
I've tested the same tubes on my EICO 666 tester using the 610 compactron adapter and the latest published Coletronics test data.  Triodes 1 and 2 test good at 110 to 120 for each of the 4 NOS tubes, but Triode 3 does not read properly on ANY tube - most likely from erroneous tube setup data.  Checking similar tubes with the 12BY basing diagram (the 6K11 and 6Q11 compactrons), these tubes call for entirely different section setups according to the Coletronics data.
 
After an hour of freezing my brain and cross-checking with the 1975 RCA tube manual, I thought I would ask if anyone else has run into this situation with the Eico 666, and perhaps learn of a more suitable test setup for the 6AV11.  
 
I acquired the 666 to avoid lugging the TT-1A boat anchor between locations for obvious reasons, but would like to have more confidence in it - even though the adapter and compactron pin key change schemes are a real PITA when compared to the TT-1A.
 
Thanks for the help!
 
Jack  W3RU