Engine Type number on 67S

Guys, A friend asked me a question about his 70 T coupe with a 67S engine. The engine swap was done before he bought the car. I did not have an answer so I ask the question here:
What does the four digit number 6925 stamped in the case just below/behind the 901/02 engine type number mean. It is stamped within a half inch of the type number and is not the serial number. The serial # is 960927.
Second question: Can old style tensioners be re-built? If not, what are the options? Install new style tensioners? What about oil feds? The right side tensioner in this engine is failing.
Thanks for the help.
The Capitalist Roader
73S sportomatic

I have never been able to figure out what those extra 4 numbers stamped below the Type # mean, and it was discussed here earlier with no resolution.

As far as the tensioners go, I replaced mine with the 930 tensioners when they went. It is a much bigger job to do the pressure fed tensioners on the early SWB cars, since the cam chain covers must be machined to accept the oil line bosses, and the 930 tensioners are adequate, cheap and fairly reliable in the smaller 2.0 engine, as it does not make the kind of heat the later, bigger displacement engines generate. Be sure to replace all the chain guides at the same time.

TT

Tom,
Thanks for the reply. I am trying to help a friend who is just getting started in Porsches. I must say that it was a surprise to open the lid on his 70 T and see a 67 S engine. Not sure if the guts are still 67S as there are some serious tool marks on the cam nuts. All of which tells me that the engine has been apart some where along the way.
Thanks again for helping a friend.
John Meyer, aka the Capitalist Roader