Michael,
I hope classic revival have a BIG engine bay. The 4.6 quad cam ford motors are MASSIVE - if you ever see one beside a 460 big block Ford motor, they're similar in size!!!!!
I'd seriously get your friend to measure around the front chassis rails to make sure that it's not going to be a big re-engineering exercise just to make the motor fit....
I may be way out in my estimation, but a "budget" twin turbo motor could well end up costing less than a Vortech (or other centrifugal blower) motor, not to mention what AEC are asking for their PD blower kit. As an example, the Vortech on my motor is currently selling for a little over $6,500- on it's own - no brackets, no pulleys, no belt, no fasteners - NOTHING. The smaller Vortechs are cheaper, but you'll still have to fabricate everything to suit a Lexus. You can see how it quickly adds up. If you go ahead and buy the latest ball bearing turbos and a huge Garrett intercooler then it'll cost you big bucks, but the second hand Nissan turbos seem to work well on the Lexus motor. You're going to have to fabricate headers anyway, so the turbo piping isn't such a burden. The technical side of things seems to only be an issue if you're trying to run way up in the boost, but a 6 - 8psi boost limit would show excellent results without causing any problems.
GET THE TURBOS!!!!! (Then ring Scott and politely ask him to make it all fit.....
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