All those pipes!! Long range tank in cruiser

I've found a reasonably priced 150 litre long range tank out of a 55 series cruiser. [$40!!] I'm going to fit it into my 88 troopie HJ75. I've just about got the mounting of this beastie worked out. Are there any pitfalls to fitting the filler tube? I have one from another vehicle and have worked out where to mount it on the body. Are there diameter requirements, or angle/fall requirements for the tube? How about length? Can an exhaust place make up the tube or is it of different standard to exhaust pipe..? AND ALL THOSE OTHER TUBES!!! I have that plastic dohickey where lots of the pipes end up and even have them sitting in line to work out where they go..... just poke em on?? THEN to do the rest..... I'll probably go to a professional and suffer the embarassment of my 'back yard' fitting. ... then get them to wire and fit the rest. Perhaps I could go all the way. I guess I could mirror the set up that is already there. Add a new guage, and simply have a tap to switch from one line to the other. Its a long way to the back, perhaps I need to use an electric pump to help.... By the way I also have a 200 litre long range tank from a 60 series which I can't fit...... paid $450 for that one so I guess I shouldn't be so smart about how little I paid! cos this one doesn't fit.[damn] So any comments, or ideas? Great forum. Cheers Royce