The ebay kit is Lance Nist's. He did a similar dual turbo conversion on my first Pantera in the early 1980's. It involved a rebuild of the 351C incl. forged 7:1 pistons and crower cam.
It used early turbo tecnology and was a PITA to keep running well.
Mine ran about 14 psi on then available 95 octane gas. It ran 117 mph in the 1/4 mi., and this was typical of other Nist turbo panteras.
That seemed fast at the time, but my '03 Z06 corvette does that stock.
IMO, I'd pass on the ebay kit.
Either build a strong NA engine or have someone who knows what they are doing build you a turbo engine using modern EFI and engine controls($$$).
Just my opinion,
Jack
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