Tom Walker wrote in a message to Roy J. Tellason:

-> TW> I have two Subaru's and ht Chev S10 Pickup.

-> Hm,  I would guess group 25 or 35 for the cars,  maybe 24 
-> (cheaper),  and a 75 or 78 for the pickup,  though possibly a 70 
-> would work in there...

TW>  Group 35 and 75 is what the Charts recommend. 



I haven't done this for a living since 1995,  it's nice to know I've still
got it to that extent.

A 25 is like the old 24,  but slightly shorter in the length.  I think it's
9 inches overall instead of 10.  A 35 is the same as a 25 but with the
opposite polarity,  or like a shorter 24F.

A 78 is the same proportions as a 75,  but slightly longer.

 TW> All there are still in good shape so I haven't checked out 
 TW> "Additional Fit" sizes yet.

You may find that in the case where there's a 35 in there you have room for
a 24F.  And where the 75 is,  it may fit a 78.  It's only needing one
additional inch,  after all.  Me,  I kind of prefer to go with the biggest
physical case that will fit in there.  The reasoning beind that is that to
stuff similar capacities into smaller boxes they have to make the plates
thinner,  which is going to make it somewhat less rugged over the life of
the battery.  That's why I had a 31 in my old truck,  because it'd fit. 
  And the truck I have now has a 24 in it,  pulled out of a car I
used to have and bought new for that car.  I only need about 350CCA or so
to start that motor,  and it's a 525,  so I should get at least 5 - 6 years
out of it,  especially considering that I don't run that truck all that
much.  When it comes time to replace that,  I'll probably put a 27 in there
(12 inches long) unless I can fit a 31 (13 inches long)...

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