This is a case of pay it now or pay it later. That's a heluva lot of engine to cool without a lot af surface area and the fact that Walker has their 4 tube Z-Line make the amount of time spent running around, trying different combinations is a waste when you could be out driving. I too had that bright idea when I built my 'bucket, and tried to work with a couple of local radiator shops as well as my friendly "recycler" then gave up and bought the Walker. The nice thing - it was warranted and a leak appeared after 4-5 years. It cost me one way UPS to their shop - and I believe they shipped a new one back. There are other suppliers, but Walker is 'my supplier' - the AVATAR car has one too.