Suby-conversion advice?

[Mikey]

I have a few ideas I'd like to toss around for getting my coolant from the front to the back. Ahem...

1. Run round tubing inside the main tunnel. Send and return. Pro- Neat/cleaner look, practical since everything else is in the tunnel Con- Tight space, and I havn't figure out a good way around the rear torsion.
2. Run one pipe inside the tunnel and one on the passenger side. (right next the tunnel) Pro- Not as clean, but clean. Con- A big hump on the passenger side of the tunnel, and the rear torsion.
3. Square OR round tubing under the car. Pro- More room than the tunnel. Con- Might limit ground clearance, and I'm a little uneasy about the pipes under the car.
4. Heater channels. Pro- Clean! I can check for rust while I've got them open. Con- A lot more work.

I'm thinking either 1-1/2 or 1-3/4 diameter. The radiator inlet and outlet are 1-3/4. The engine I don't have yet. I can always get an adaptor to a smaller diameter for the rad or weld a smaller diameter pipe on it. (I love TIG ) As for material, Aluminum, Stainless, and Carbon Steel are all options. But the cost might be a limiting factor. I have the capibility of welding all. I kinda want to say away from copper. Question... Would a smaller diameter pipe put a strain on the water pump by restricting the volume of water it can move? I'm an aircooled guy.

I'm sure I missed a few pros and a cons, But I've just gone blank on some of them. And please excuse all spelling errors.

Let me know guys. I'd sure love to have another perspective on this.