I just ordered a Dynomax 3" cat-converter from Summitracing (http://www.summitracing.com). Any experiences? They give a 90 day guarantee - whatever that means.
I also considerd a Catco cat-converter, which has a 25.000 miles guarantee, but in the end - ended up with dynomax.
I'm having a new DP made and the cat installed to the bottom part of the DP - a littel lower the the original one. So no cat under the car.
I had another brand installed on my supra. The only issue was the first place I went to didnt want to install it. I-club might be the better place to ask.
Off-topic, I know, but I have to ask -- Ciper, you have a Supra? What year? My brother and I just finished swapping a Cressida 5-speed transmission into his '85 Mk2 to replace the automatic. The previous owner put in a JDM 6M-GE, and the current plans are for some light boost... :)