Questions about moving a gas tank

[oleguy]

I am concidering moving the gas tank out of the cab of my 1967 short wide C10.I have a couple questions.Question (1) If I use a Blazer gas tank mounted behind the rearend, how much will the back of my truck go down with a full tank of gas, and how much will it come up with a low amount of gas? And how can this problem be fixed? Question (2) Is there a gas tank from another vehicle that will fit foreward of the wheelwell? Keep in mind this is a short wheelbase 2 wheel drive pickup. Any other ideas will be considered,and appriciated. Thanks oleguy