Doesn't mean it's not a great way to go. Have Tim Meyer stroke it to 434 cubic inches and go for TQ instead of RPM. It's strong off the line without reving and by keeping the revs down the engine is bullet proof.
We set mine up with a mild cam concentrating on TQ. We did 500hp with a limited 5500 rpm. 534ftlbs of TQ . . . but it made 434 foot lbs of TQ at 2000 rpm. I wouldn't call it a race engine but I would call it a fun engine.
Intake will be spread due to the extra inch of deck height so a good intake will be a challenge. Mine was originally ran with 1" spacers. I bought a Weber setup with a Hall intake. I ended up cutting the center out and widening the manifold. Worked well:
Quicktime makes a bellhousing for the 400 to ZF but it is inverted for the GT40. I am unsure if there is a current bellhousing for the Pantera (Zf) orientation).
The ring on the quicktime could be cut off and re-welded 180° but would have to be done with precision. You would need to make sure you dial in your bell housing but that should be done anyway.