s1 fuel tanks to run fuel injection

[s1v8esprit]

I want to change/modify my fuel tanks in my s1, I plan to use fuel injection on my v8 and would be great to get some better fuel tanks with a built in swirl pot and larger outlet/inlets. Could I get my steel tanks modified? or will I have to get expensive alloy tanks made? I have limited funds and I don't want to go with the lift pump and external swirl pot route as its extra pipe work and clutter I don't want! do the latter esprit tanks fit?