Rear mount tank options
 

Looking for all options for an inside frame rear mount tank.

What is the best fit for the money? It's going in my 72 K 10. I would like to just use a blazer/suburban factory style tank as I assume they will be most cost effective. But how well do they fit and do they need bed modifications?

Also if I go factory style how big can it go? I remember our old suburban had a 40 gallon tank!

I did a quick search but couldn't find what I was looking for maybe there is a sticky? Or should be?