Well, I have begun construction of my 6MB8 amp. I purchased some Svetlana 6F3P tubes as they were noted as replacements for 6MB8 and ECL82. Well, the Svetlana data sheet for 6MB8 is somewhat different than several other sheets for the 6MB8 and ECL82, and even old Soviet 6F3P tubes.
For example in the sheets that are similar, the triode anode current at grid at -1.5v is about 2.75mA in several sheets. In the Svetlana sheet, the same conditions indicate the tube drawing about 3.5mA.
I am a little confused and contacted the seller, but I do not know if they would even know. I am going to proceed with the build as specified by Steph, but want to reach out for some guidance.