[brownbear]

that set up looks fine to me. Stay with the stock exhaust if it's in good shape. Removing the muffler will help reduce the temp.

My truck has 2 inch off the turbo as it mated the flange and I had some serious bends to do prior to getting under the truck. But immediately below the engine I go to 2.5 inch.

LIke dougal says, fine tune it later. Enjoy the air it will breathe.