Off the top of my head (empty at times!), I seem to remember several C-Brats changing out their old 18 gallon tanks for the new ones. Cost awas about $500-600 for the tanks, new hoses, clamps, cleats, etc. New bracket/cleats had to be added/fabricated for the new tanks, as they were of a different configuration.
There are some threads on tank replacement in the
Fuel Systems section of the Forums/Library for the looking! A specific one is
I'd Like Bigger Tanks.
Of course,
all the fuel lines, including the inlet and vent lines, should be changed out every so many years, say 5-8 years (fuzzy memory here).
The lines all have manufacturing dates on them so you know their age. They get brittle, crack, and leak with time. Even if you don't replace yours, check their age and condition out. Cracks are more likely at bends, especially tight ones (which are a no-no), and where the hoses enter the stainless steel clamps. The clamps should be doubled for safety according to manaufacturers association standards.
Believe it or not, here's enough energy in your gas tanks to raise your boat many miles up into the atmosphere! Please don't join the...
MILE HIGH C-DORY CLUB :smileo
Joe. :wink