2-channel you might, might make it at $500 if you used a single chassis and by doing so you risk trafo induced hum. 3-ch figure $700+. And those would be barebones cheapass parts builds. And figure it taking you ~40hrs or so to build it. I think thrice is crazy for doing it for as little as he charges.
You lost me, I'll have to reread everything later.
No, you couldn't, trust me on this.
2 or 3 is fine, I've never tried to figure out which I prefered. And no, I can't think of a good reason to use the balanced outputs unless the 840 does something crappy to create the single ended signal.
There's also the very real question of when he'd be able to do it. Far as I know he's still working on the last batch and hasn't opened up the ordering process again.
Also, since it seems unclear, does the OP want single-ended or balanced?
I can tell you one thing for damn sure, there's no way they'll get me to pay for this one without listening first. St Anger remains one of the few CD's that I listened to once and then never again. It was truly terrible.