ATM: Focal length adjustment.

[Eli Vandevoorde <elivv@efn.org>]

I've begun the serious work on my mirror - an 8" f5.75, and have completed
10 wets of #180.  The focal length is now much easier to find (within
about an inch), and I discovered (imagine my surprise) that I am about 6"
too short. 

Will I be able to make an adjustment that large in a reasonable amount of
time working TOT with #180, or should I go back to 120 and work it off
there? 

Eli VV
Coburg, OR