I looked at it. I lived through it. There were some very strong, very talented full backs at the time.
You talk about the standard of the competition and them being part time athletes. Lockett was a part time footballer too wasn't he? They were all on an equal playing field. Comparing an athlete today to the players back then is silly. If you placed Rance back then on Lockett, he would be a part time footballer too, and he would play entirely one on one in open forward lines. Place Lockett into today's football, and his quick leading and physicality combined with today's grounds, tactics and fitness regimes could very well still see him dominating.
If you want to time travel, you have to make the appropriate allowances.
Interesting how it's silly to point out that modern footballers are better than part time amatuers from a suburban competition, but when you say the part time amateurs are better it's not silly? For... reasons ? Nostalgia? Things were better back in my day?
If you don't want to compare that's fine, then don't say the amateurs from the 80s are better than today's players. It's a two-way street.