Hi everyone, I have a 50-th Campy group heading to me, currently in transit. There is no freewheel
in the set. So my question is what kind of freewheel should I (or can I) use. How many speeds will
the rear der. and the friction shifters handle at the most? I have 6sp, 7sp freewheels in my parts-box,
and even have an 8sp Suntour freewheel. Which one will I be able to use?

More importantly, what are you putting it on?

Either my Paramount or Gold Colnago.

The dérailleur and shifters for that era, it was 82' or 83', should be able to handle as many cogs as the spacing allows. Frames and hubs of that era had 126mm spacing. Hubs of that era had the old threaded freewheel mounting. If your freewheels fit your hub any of your freewheels will work. If you use the 8 speed you might need a narrower chain, perhaps. Even a cassette hub, the ones with ribs instead of threads, would work as long as it has 126mm spacing. Sheldon Browns web site might help. Check it out.

I think the RD will work in friction mode up to 8 speed, maybe further. 6 and 7 should be no problem.

We do require pictures, otherwise it never happened.

does any of you know for a FACT that the 50th anniv. rear hub requires
a 126mm spacing? I can't depend on the era anymore because I have
two NOS Colnago frames for 82 and 83, and they both have 130mm spacing!!!
Go figure.
So my next question (naturally) is, are these two frames out of the question
for the full 50th group because of the rear hub?

All Campagnolo hubs in 1983, the year of the 50th anniversary gruppo were either 120 or 126 mm. The same goes for all Colnago frames. If your Colnago frames are truly 130, it means that they have been spread to 130 subsequently. This is not a problem however as 2 mm per side is nothing.

I have the original brochure of my 83 Colnago frame and it states 130.
I bought it NOS and I opened it for the first time, it measured 130 new
out of the box.

I would suggest buying a Campagnolo 6 speed Titanium freewheel. This freewheel is quite a special item and command quite a price on ebay but if you have the ultimate groupset why not get the ultimate freewheel. They come in a couple of gear configurations and even had a separate and specific toolbox and tool for servicing the freewheel.

6, 7 or 8 speeds? The question is what are you going to do with the bike and groupset? Most people who mount the 50th anniversary groupset on a 'special' frame do so as a Sunday-best bike - only to be ridden on special occasions (others keep the gruppo in the case and never mount it). If that's the case, the number of gears is not really an issue.

Your Gold Colnago frame sounds like an appropriate frame to show off the gruppo. I can hardly wait to see the bike with its groupset.

126mm rear spacing is suggested.

Sorry to be harsh, but rewriting history is not my thing. You are mistaken. Either your bike is not an 83 or you are making this up. NO 1983 Colnago was originally set up in Cambiago for use of 130 mm width hubs, unless Ernesto was using a magic ball. Campagnolo did not even list 130 width hubs in the catalogs they distributed in early 1984, so far be it that Ernesto could have known of their existence in June 1983 (when he would have needed to prepare his 1983 brochures). The first catalog that mentions the 130 width was prepared for the 1984 fall trade shows, where it was introduced. Either way, in 1983 they did not exist. BTW, you do know that most frames are actually spaced a few mm wider than the hubs they were designed to accept?