Torque is what these engines do well and with the right snail will be very responsive, will be good to see a before and after stock to equal length setup exhaust like Stu has done but with .48 ex and .60 Ball bearing setup. I wonder if one of those George Fury exhausts is still avail. for sale in Ozdat from someone? it looked well made.

The L16 block will handle the L18 crank straight in so maybe the L20b crank is not required? Don the L18 is shorter so timing case height needs reduction.
Do you recall if it looked clean and well done or didnt notice at the time due to too much beauty to look at?

Ruredi call Sanjay, fill in new rules then teach us whats up.
Stock cam saves a fair chunk and Im guessing Mr Morrow has
gone bigger nicely shaped inlet valves and larger inlet ports? as the exhaust ports are pretty good already with just a clean up, they sit higher than inlets surprisingly.

With the stumpy combo 850kg and possibly 200lbs of torque should be good but Don is it possible you can find if the early 2.9 or whatever it was in some Zs is still available and able to replace the 3.25 1st gear? would make for better take off with all that torque and lightweight.