Can you help to identify these frames, bikes or parts?

Anything stamped on the dropouts? What internal dia is the seat tube? English or Italian BB? Racing number braze on + external brake routing makes me think pre-90s

dropouts have campagnolo stamped on them

internal seatpost dia varies between 26.88 and 27.4 depending on where i measure them, have no seatposts to try so not sure about that

it has an italian BB

Looks like an early 80s team ordered frame. BB threads will tell you more about its' origin.
Looks like SL, if its under 1800g be happy about and don't waste your time.
If you are lucky there will be a columbus dove light stamp on the TT near HT
(if you don't sandblast it)
A lugged fork with 2" longer steerer than your HT will be nice and period correct.
In my opinion you should search for a flat lug that look like an arc as shown below.
http://www.fiataccompli.com/bike/photos/fork.jpg

It hasn't any drilled holes at BB or stays so if you want it last longer make
your own. A big one at the center of BB and the smallest that you can under the
chain stays (1" from BB) and inside the seat stays (1" above dropouts).
Its' bottle cage braze ons are too low on DT. If you need them higher
its the right time to change them.

The seatpost diameter will tell you more about its age. Measure it carefully in multiple
axis and bring the seatpost lug in perfect condition before the paint...

the weight is 2 - 2.1kg for the frame, size is 56CT 55CC
about the columbus stamp, the paint is on the frame about 0.5mm thick, it looks like it has been painted with a brush :-/, hard to see anything on it

i'm not too fussed about period correctness, as long as it looks nice, it's gonna get a modern groupset so yea, paintjob is gonna be anything but a retro look, but thanks for the link, will consider something like that when i start the build

about the holes, do you have any examples with pictures and why should i drill holes?

what's the best way to get the seattube in perfect condition?

thx for the help both, any more info i welcome!