My Dawes Super Galaxy looked like this when I got it about four years ago.
It needed a good service and clean but it all worked.
The front derailleur was meant for a fatter frame and had a big rubber shim that looked terrible and didn't work properly, so it had to go and was replaced with a Suntour Compe-V from stock.
The shifters were indexed Shimano. I couldn't get the indexing to work 100% so they were replaced by a set of Suntour Power Shift.
I really didn't like the rear rack so I swapped it with one my son had, which was chromed but at least the same construction as the front one. I later spotted a painted one of the wrong colour on eBay and bought it with the intention of repainting it. When that arrived I was delighted to find that the seller's pictures had been terrible and the rack was the right colour after all.
The rear wheel had been changed and didn't match, so I bought a correct one from eBay. It needed to be re-dished so I put it aside until I got round to having that done. In the meantime a pair of wheels with the right rims (Weinmann concave) and Campag hubs similar to the original Normandy items turned up, so I bought them.
Then a non-matching pair of wheels turned up on a forum. The rear had a fixed gear hub, which I was after for another project, but it also came with a pair of 27 x 1 1/8 tan wall tyres, which are very hard to find in the UK, so I bought these too.
Around this time I managed to find a UK catalogue and find out what components it would have had from new.
It took a while to find the correct derailleurs, especially at a sensible price, but I got a used rear from UK eBay and a NOS front from US eBay.
The last big piece was the chainset. I think the Stronglight triple was possibly an upgrade from new but I didn't like it. Stronglight 99s on eBay always seem to be extremely expensive and French threaded, but eventually I found one that had been rethreaded to 9/16 and came with a variety of rings. The biggest drilled ring wasn't really big enough so I kept my original big ring, which had the same BCD. A couple of weeks ago I managed to get hold of a suitable drilled ring and I can declare the bike finished until something else bothers me.
I'm frightened to add up the cost but I know I'll never see the money back. I also know I would have been cheaper buying one that was still original in the first place.
I don't care though. I've enjoyed the process, and having the cost and work spread over a long period, during which the bike was always usable, has helped me keep the enthusiasm up. The bike feels "mine" in a way that a "ready made" bike might not have.
Most importantly, I like the bike as it is now.