That's a heck of a price for a replacement Mikuni. Hope it works well, and if/when it does, please post your source for others.

The "pre-cat" downpipe exists for emissions reasons. Its purpose was to get exhaust gasses up to temp as quickly as possible at start-up so the main cat would function more quickly. You can do without it, and gain a good bit by using the flange that bolts to the turbo housing to have a serious downpipe made from some fat pipe, making sure the oxygen sensor is still mountable in about the same position. There are most likely some good examples on the Star-Quest board.

I mounted my intercooler in a weird position, but I haven't piped it in yet. It sits at about the same angle as the front section of the front skid plate, tucked up as tight as possible. I probably won't get great airflow over it, so we'll see how it works out.

John B.