Well whatta ya know; here's one I can help with.  Mine was just finished last week.  The bottom of the round plastic has to be ground off to fit over the booster.  I just had mine done by Ramses who is a protegy of Mustang Steve.  It looks good and works good.  I had to get the longer cable which Steve has offered for several years.  I can send you pictures if necessary.  The longer cable was necessary because of headers and routed nicely in front of the oil filter.  Clutch is awesome!

Definitely not.  You cannot move the block/cable hole upward or the cable will be right on the cowl floor.  It is a big balancing act and everything has to fit exactly as designed. 
Loosen the booster studs and push the booster downward just a little.  The adjusting wheel will likely touch or just barely clear the booster.  There just isn't room in the whole system to move anything downward more than that or the brake light switch will not be able to clear the steering column.  You still will likely have to dent the column tube depending on which booster you have.
You will remove the black rubber piece from the cable before installing it into the billet block.

Loosen the booster studs and push the booster downward just a little.

Worst case you may have to loosen the two bolts if you ever need to adjust the cable, then retighten after adjustment is made.

Do you have the two vertical bolts into the billet block yet?  They will pull the block upwards a small amount.  I have seen these installed with some clearance and some where it is touching the booster.  The clutch will work either way.  If there was some way to have given it more room, I sure would have move it, but there is just not enough real estate there to move something one direction without affecting something else.

The booster is originally a Ford Fox platform design that was used on alot of vehicles.

Yeah, well...  That's why that instruction manual and CAD drawing with those big holes are drawn the way they are.

People cannot appreciate the amount of time it takes to develop something like that, with all the trial and error, remove and refit, compromise this and that, etc to get something that will work.

But everyone has a better way to do it because they do not know about all the pitfalls of doing things differently.  I am definitley not trying to say that my designs have no room for improvement, but they will work without costing you a bunch of money.  IF... well you know the rest...