Sorry I forgot about the part number anyways its 2466 they are $156 from summit racing. As far as the ac goes the monte brackets will be the same and I think if your buick came with a 3.8 originally that a small block chevy will bolt to those motor mounts, but don't quote me on it. I havn't took any pics of under the hood yet but I have some exterior pics on my website @ http://firstname.lastname@example.org
I will take some soon so check back on my site. I had no problems with the headers fitting. I installed them with the engine in the car from the top quite easily. Check out how I had my exhaust dont. G-body crossmembers only have a hump on the right side so I used a magnaflow 2.5" dual in/out muffler. This mufller is basically a x-pipe with baffling.