my friend tells me to replace the short piece of exhaust tube between the manifolds and the cats as this is the worst part of the factory exhaust. is this difficult for an exhaust shop to do? seems it might be tricky to weld a new piece to the tapered cone entrance of the cats-any opinions? or could i delete the cats altogether? (where i live there is no emissions testing) would removing the cats effect the fuel metering or screw up the eec in any way? any opinions are welcome as i would like to have less backpressure in this lousy factory system. thanks gary o.