Billet servos, frictions, and bands
You definitely want to upgrade the rear (the low/reverse) servo but if your running a manual VB you don't need to worry about the accumulator because it bypasses the accumulator. There is no intermediate servo (see my edit below) in a torqueflite, just front and rear. I always use stock old style front servo's. Haven't had any issues at all with them but if your original servo is worn a replacement is in order. I also upgrade the front servo band strut. Haven't seen a reason to upgrade the anchor but maybe someone else knows something I don't. Can't get the links to come up so I'm not sure exactly what they are but I usually buy my billet rear servo's from Mr. Randy on Moparts. Quite a while back Rick Allison at A&A recommended the blue friction plates so that's what I've been using, but I haven't read much on the differences so I can't comment on what might be better. I just know the blue plates last real good for me. Not sure if their the same compound as the green ones you refer too. Sorry, not much help there. As for band type, I've read about the Kevlar bands being hard on drums also, plus they tend to glaze over quicker in street use. I've used red lined bands with great success. I've read some guys like to use flex bands to take up any irregularities in the drum. Personally I feel if the drum is out of round it shouldn't be used so I prefer rigid bands. Plus they release quicker so there's less chance for 2-3 shift overlap.
Look up your manual VB and see how many front clutch spring it calls for. They vary and I use what the VB says to use.
Build it with good parts and blue printed specs and you won't have any issues. IMO something built to that order has no trouble standing up against 700+ hp. Even stock friction plates and bands built right are good to 550+ hp.
Don't forget a good bolt in Sprague.
Is that a roller cam your referring to? Does a big block have a cam thrust plate like a small block? If it's a roller cam you either need a thrust plate or button.
EDT: I see the PATC site refers to the front servo as the intermediate servo. It's the front band servo which is the intermediate gear so I guess it's a matter of terminology.