Stock 318 Headpipe pictures (in car)

I believe that I answered your other post and included some pictures of a system that is out of a car. I don't have a lift or any way to get you pictures from at the proper angles that you are looking for.

But I would think that the stock 340 system would be a good guideline for what you are trying to do. My systems are 2 1/4" all the way, without any bottle necks to get through thight spots.

You may also want to let us know if you are running the 90° oil filter adapter or not as that will affect the routing also....

Any good exhaust guy should be able to get one to fit, or have you tried the mail order kits?

I've seen people using larger than 2 1/4 all the way back, I don't think that you should compromise and go down to 2" and restrict your flow because your exhaust guy is not capable of accomplishing this. There are better systems available.