Yeah I think I've heard of a couple. All you need is time and skill to do all the fabricating for the mounts, plumbing, etc. Frankly if you're just going to drop in a run of the mill 350 I'd go with the 7mgte route instead. It's basically a bolt in motor swap, and just as potent a motor. You can buy a kit from Don C to make it an even easier swap yet (or have him do it for you). If your looking for mega hp in the end it might be cheaper with the small block and go through the extra hassle of fitting it. After about 450-500 rwhp uprgrades on the 7m start to get really expensive.
Aaron I
Aaron I