My question is I have a 1999 Ultra Ground Pounder and I wanted to put a larger/stretched gas(4 to 5 gallon) tank on my bike and was wondering if anyone knows what type to buy and where to buy it? This is my first bike and need some help. I have seen a few on E-Bay but again not sure what to look at. The photo of my profile is the bike I'm referring to. Thanks in Advance!