You're on the right path: Max out what you can do with a stock tank before you even start to worry about capacity. There are A LOT of things to sort before you get there.
Long version: There is no safe middle ground in Lemons assessment. The second you start monkeying with OEM fuel stuff, you introduce a new and almost categorically unsafe variable (you). We trust Lemons people in a lot of things, but tinkering with the primary fire-causing component of a car is not generally one of them we take lightly. Go ahead and ask Pagel; he might agree, though I suspect the answer is officially a no.
Ultimately, we know people drop fuel tanks to get years of gunk out or to replace pumps or a variety of other things. The fuel system is budget-free upstream of the injectors...if you have to take the tank out, look over every part of the system—fittings, hoses, high-pressue lines, filters, etc.—and replace things that need replacing with high-quality parts, do it right, and don't half-ass it.
Edit to add: That last paragraph is NOT an endorsement of swapping out bigger tanks. It is a word of general advice for anyone who has to drop a fuel tank to fix their crapcan. Please, please do not f*** with your fuel system unnecessarily.
Eric Rood
Everything Bagel, 24 Hours of Lemons
eric@24hoursoflemons.com