I completely understand where you are comming from, I would be thinking the same thing in your position
Part of the point was to get as much info as possible to judge wether its a relistic undertaking. Belive me I was never under the islusion it would be easy!
Something that has just popped into my mind is bending the tubing, major problem. Still im a sucker for punishment and would still like to gather as much info from you helpful chaps as possible so I can decide for myself
PS. I have not welded before and wouldnt be doing the welding myself, hence the lack of know how on the subject.