Quite correct that's why he went for a Yanky one. It was the 6.354T (turbo) and I must correct myself, it was a 5 speed ZF he was fitting. The E type g/box was mated to a 4 cylinder Perkins 4.203 I think that was in another Mk10 that he used as his daily runabout.
Don't know why he thought he was going to get 150 MPH. 6.354T only had 165 BHP slightly less than my BMW 2.5 with the chip fitted. Standard E Type 3.8 had 265 BHP and only just managed to nudge an E Type to 150. 165 BHP in a Mk 10 no bloody chance.