when is 20 degrees SQUARE?

["John Dohrmann" <jdohrmann@domain.elided>]

Since my 86 spider is now running with the new oil pump and distributor
(waiting for a VVT mount), I'm planning a complete brake job.  TWO questions

1.  The service manual says "Using a square guage with a 20 degree corner,
verify the exact position of the brake operating pistons."  Now, when I took
geometry, a square guage would tend to 90 degree angles.  Can anyone explain
this to me in American English?

2.  Since I have some pulsing, I need to do the rotors.  Can they be
machined easily or am I just better off ordering rotors?  I don't have any
leaks so am just rebuilding the calipers myself.

By the way, I retorqued the head bolts -- having completely drained the
block by removing the plug under the exhaust header, and every head bolt had
water in it.  I assumed someone had flooded the spark plug well while
"detailing" the car for sale.  So instead of just loosening them one turn, I
took each one completly off and wiped the nut, washer and theads dry before
oiling and installing/torquing.

John D
'86 spider quad  (looking for a silver hardtop)

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