tell me about it that pic was took at about 3am and it was -2 with no heating in the garage your such a slave driver mark. also had new cam belt to durring the swap.
if you just say you want it quiet the can do it without restricting flow they just need to use straight through silencers maybe a large one at the back and a smaller one in the centre.
I've been running a ported mani for 12months now when doing the porting I had a jam mani to copy ;) and it's been 100% so far. You will find gains from de-cat as even the gutted cat has restrictions in it as I found. But this is not essential.
eBay is your friend mate you just need to measure the hole in the wheels then get it to 54mm hub size think mine were 74mm to 54mm on the schnieders. I got short wheel nuts of egay to the D1's about £30-35 I think ;)