OK I've successfully re-strawed the pieces that were originally done this way. Ready to re-assemble, but I can find no indication on assembly lubricants. I have an old Luger manual reprint which doesn't even mention oils. I know that too much, in the wrong place, is a disaster.
So what is the consensus from the experts ? Type of oil, and where to use ?
Thanks

You're never going to get a consensus from the experts on oil, whether discussing Gran Prix cars, sport bikes or Lugers. But just to get you going I'd recommend wiping all the metal with an oily rag and putting a drop or 3 on the actual metal-on-metal friction points. Don't oil soak the grips.
We used to joke that if you had gun oil dripping from your glasses after shooting your 1911, that was just about right. But we may have been taking it too far.
dju

I've never shot my C96s at the range, so when I occasionally get them out of the safe I just wipe them with oil and I put one drop of Ballistol on friction points.

With CZ, GLOCK, and the 1911 that I use at the range I dab a bit of Tetra Gun Grease on the main friction points and outside the barrel.

Sergio

I put a dozen drops of 3&1 sewing machine oil on a shaving brush to generally oil parts. On the underside friction parts, rails and such I smear on a little white lithium grease if I intend to shoot it. I don't think it takes a miracle oil..just a good oil often. Once the weapon is assembled I wipe it down lightly with a rag.

I use a light grease(TW25b) on the bbl. extension and toggle train where they interface, and then a good gun oil to the other friction points where steel meets steel. A wipe-down with a silicone oil lambs wool pad to the exterior......works for me and all of my guns.