Largest group battery that will fit?

[AuroraGuy]

Does anyone have any idea for a 00 GAGT - what is the largest group battery we can fit w/o any modifications to replace the stock battery?

Mine is finally dying and I usually replace an OEM with the biggest fattest battery I can cram in there :angel


Thanks :-)

-JD

[tenspeed]

I got a Optima Red Top 75/25.

I found a used one on ebay for $70 shipped.