if it were cam related, it would probably occur once every other revolution but it sounds like it's every revolution so more likely directly connected to the crank/flywheel/clutch.

i don't like that sound at all - definitely an interference (parts hitting each other) or oversized clearance (something too loose).

 

it's a pita, but you can drain it (save the oil) pull the pan and turn by hand to check the bottom end.

It sounds like Ill have to get the wife to crank the motor by hand while I investigate.  I didnt measure but if I had to guess I am seeing interference at every 1/2 rotation of the crank.  I do have an automotive stethoscope, I'm sure it will come in handy.  Ill also try and get in touch with rebello today, I dont intend on tearing this down myself if theres some fatal flaw within it.

How far are from Rebello's shop?

Its like 60 miles from my house to Rebello, and I have a big arse truck to tow cars around if needed..

That's not too bad. I was just thinking it would be nice for them to hear it in person...

Clucking sound solved! One of the clutch slave cylinder mounting bolts were too long and rubbed against only part of the clutch causing the intermittent clunking. The bolts were in the car when I bought it and did not rub on the OEM clutch so I'm not sure if these bolts belong here or were incorrectly installed by the previous owner.

What a relief.

Good find

Don't ever trust my hearing-

Good investigative work!

That's great news. You must have breathed quite a sigh when you found that!

Even the wife jumped up and down a little.  The key giveaway was seeing orange paint flakes in the starter hole, the clutch is a centerforce.

 

Haha!! It's great when your joy is so apparent that it's infectious!