Here is another potential snag with trying to use the earlier heads with the new block. The front oil return passage will not seal with the earlier head and gasket. We may be able to work around this one though, with some epoxy sculpting or welding.
oil  ^
oil ^
PT turbo intake .
2.515" wide
1.225" tall
There is a lot of stuff to compare and information to digest.

Let's not make any hasty conclusions about theses changes until we check it all out.

The mechanical parts, so far look to be stronger and better built
Though the new rod is better, ... it is not up to the T-2 level, by my visual estimates. Time will tell.

This new timing wheel may be a blessing for a better ignition system. These decisions will need to be made by some people more skilled in the ignition systems.
Here's another strange deal, look inside the left piston. .....      How does the oil get out of the oil ring slot?
On the right piston, there are two slits on each side of the piston, the oil is to escape from. ... is that enough?
^            ^
This piston has a small oil ring. The top ring is seated in an iron jacked ring land.
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