Supercharged? I went to have a good look at one some years ago, and regretted not buying it ever since
I just fell off my chair laughing. Have you've never seen under the bonnet of the V12?!! You cannot put a can of coke anywhere, not to mention a supercharger... The normal fuel injected produced 350Bhp (a lot for the day) and returned nearly 12Mpg, 14Mpg down hill, but most of the time single figures as I drove it like I stole it.
Lister (or AP Automotive) did a few engines as I remember, certainly one 7 litre engine, and one with twin scroll superchargers. The one I looked at was one of the supercharged ones, there is at least one on sale on the net at the moment. POA........