Say a fella wants to build an SET monoblock based on the 300B..


Could you point him in the right direction or where to start. I see a kit on ebay but not sure if that's legit or not. I don't own the speakers yet and plan on building my own that would pair up well with the amp. Any help appreciated.  
I think you're in the wrong forum.  You might try the Amp Preamp Forum here on Audiogon, or better yet, go to Audio Asylum and look on SET Asylum or TubeDIY Asylum.  There are more knowledgeable builders there than here, by far.  More advanced is DIYAudio, a separate site.