Question about large dealer installed gas tank

[1956cameo]

My 72 suburban has one of those large home made looking gas tank that was dealer installed. It is the type that has large carraige bolts that go thru the floor and the tank. For all the other people on here that have the same tank I have a question.
When I got my suburban the tank was taken out and the rubber lines were missing. Well thru piecing the rubber lines that were in the back of the suburban together I was able to figure out where they all went (I thought). Any how I put everything back together with new lines but now when I try to fill up the gas tank with gas it burbs horribly spitting gas out onto the ground. Does anyone know where all the lines are supposed to go. It had 4 or 5 vent lines coming off of the top of the tank but they obviously aerent working.
Also does anyone know what I could do to simply cut a line so it can vent without it having gas splash out. Any info would be greatly appreciated.