There are a couple of theses swaps documented here on the forum. If you look in the upper right-hand corner of the forum, there's a "search" box. I put in Buick V8 and got quite a few hits. Here's a good one that I dug up.......
viewtopic.php?f=1&t=27856ks_skyhawk also has done this swap.... try searching his posts or PM him.
I think apollo455 has also done one, too.
These are the only ones that I know of, but there are several hits from the search button trying.... "Buick V8", "SSB" (small block buick), "Buick 350", "Buick 455", etc...
Some more searching .....
viewtopic.php?f=2&t=30284&start=7...... one more....
viewtopic.php?f=2&t=27542Seems to be a lot of discussion on the topic, so just start digging.
By the way, my Buick 215 V8 swap doesn't apply here, so if your search hits on the small, aluminum Buick 215 V8.... it's not the info you're looking for, as I don't think any of it's mounts will work. I know the bellhousing bolt patterns are different.