improved spark gap reports

Out of curiosity, I made a new spark gap using the Victoreen SGCA-2500
spark gaps from All Electronics that someone on the list mentioned
several months ago.  I got a piece of thin acrylic and drilled 1/4"
holes spaced properly for the cylindrical ceramic gaps. I then wire tied
them to the acrylic and soldered all 8 of them in series.  The gap is
MUCH quieter than my old two bolt one; now the primary noise source is
the secondary output.  Spark length increased by about 4" and quenching
is apparently tons better as I can run the coil for several minutes with
no length degradation.  Total gap construction time was about 45 mins. 
I will try to post some pics of it soon.

My next target for improvement is the RF ground.  We have an inground
sprinkler system that splits off into the ground right where the water
main comes in.  Seems to me like this would be an ideal connection point
for a RF ground.  Any possible problems (other than having the house
electrical ground also possibly connected to a water line)?  The
physical proximity of the sprinkler pipe is ideal and driving ground
rods are probably not gonna happen. Would 8AWG cable be ok for the
ground wire or is copper strap the only thing worth it?  Total run will
be as much as 25ft.  Where can I get strap and about how much does it