I've had a lot of 1978 advice recently (born jan 79; now expecting dc1) ...
Mum had kept her books, and frankly they're hilarious.
Agree with pp that smoking told to keep a minimum, but not to worry too much, alcohol, well, just try not to get too trolleyed too often. Always in terms of making mum feel bad, not badness for baby.
Food wise, no real restrictions at all, although diets in general less broad than now. So she doesn't understand why I won't eat soft cheese, pate etc (although these are mentioned in her books, just weren't on her radar then, I think)
A lot more "take to bed an and do what your doctor says" She worked on 1st sept then left as had a small bleed. I was born 4 months later. I currently have about 4 months to go, and she can't quite believe I still feel fine, and am planning to carry on with work to 37 weeks if all goes well. She's very anti us buying anything for the baby "just in case" as she's pretty sure I'm damaging the baby by keeping calm and carrying on, which is driving me potty.
Bottle feeding all the way as I was in scbu. Baby looks thirsty in between, then give boiled water (and gobsmacked that dsil doesn't give her bf dd water in a bottle at all!!!) Front sleeping, and to transport a baby home from scbu? Loose carrycot on back seat of car!
It's a wonder I've survived to reproduce; but I get the impression us kids of he seventies were made of pretty strong stuff! Our doc probably are too, but not up for testing it out tbh!