Thanks Enoch.
I took a look at your site and I can see what you've done with the manifold - not sure what I'm going to do with mine yet. I fancy throttle bodies but have no idea how I'd attach them.
I also found this picture of a Scorpio with the 8v engine -
http://www.flickr.com/photos/stuart166axe/3130836319/ which looks very similar to the Sierra manifold so I don't think it is going to be any better.
Matt