All are easy. The only hard part about the shocks can sometimes be getting the old bolts off.
The muffler and tailpipe are very easy. If you don't want a full tailpipe, just use a turn down on the outlet side of the muffler.
You might want to check out Waldron's Exhaust on the internet. They will sell you just a tailpipe if you call and ask at a very reasonable price. They don't advertise that on their website. It will appear that they only sell the entire exhaust system. I find their quality and service to be excellent. Freight might appear high, but when you call them, ask them about shipping through Fastenal to the store closest to you. They'll do it and it cuts the freight cost by at least a half.
I have found the best price on mufflers for these trucks at Rockauto. The last couple I bought from them were Wagner. The price was $40, but they had a $30 rebate bringing the final price to $10. Shipping cost more than the mufflers!
Matt
