When I was a lad, we never had chain stretch measuring tools either, so nobody ever needed to replace their chain. There was no Muck Off, so you didn't need to clean your bike, but there were loads of little oil caps (anybody remember them?), which you flipped up and squirted in your 3 in One oil. There was no such thing as a bike stand, so all servicing was done with the bike upside down. Life was so much easier then - and less expensive.
When I was about 15 years old, we made an adjustable spanner in metalwork at school. I bought a completely dismantled Triumph Tiger Cub off a guy, and I rebuilt it with more or less that single tool as I didn't have any others.