I'm no purist... That looks like a job well done.

Have you looked at what it would take to stuff a shortened
240 front end under the hood and between the fenders of a 140?
The 240 is a 140 that volvo revised to allow V motors, mostly
by changing the front suspension around.

For the expense and trouble, I'd say you're probably better
off starting with a 75-80 242, not because the 140s should be
saved but just because the 240s were set up for the V6 or I6
from the start.

How much more nose heavy is it that way? What are those
manifolds from?
chris