Upright pressure bar

[Lance Lafargue]

I saw a piano today that had been restring by a PTI (piano technician
impersonator).  One of  MANY problems was the pressure bar not being
tightened down enough and the strings were then badly spaced.  I could
squeeze the unisons with my fingers and easily move them around.  
QUESTION(S): 
1)Should I lower the tension (it's 80 cents flat) then tighten the pressure
bar, or can I tighten it without lowering tension? 
2)How should I decide how tight is tight enough when I don't have a clue
where it was originally?  (How much angle do I need?)
3)When restringing an old upright, how do you (ya'll in the south) measure
it's original height before destringing?  Do you use a ruler or use wedges
like measuring plate locations, or what??  I assume that you all remove it
and replace it after restringing.  
I'll probably regret working on this thing, but this guy's grandmother and
great-grandfather played it and family members were "ghostwriters" for
"stars" years ago.  I wish so much that you could all see what this PTI did
to this piano when he restrung it!  We could all have a "chin wag" over a
stout and yuk it up!!!!  THANKS
Lance Lafargue, RPT
New Orleans Chapter
Covington, LA.
lafargue@iamerica.net