Thanks for your reply.

I actually had to take the car to my trusty Volvo specialist yesterday for other matters and asked about the plugs. He looked at them, saw that I had unscrewed the little metal things from the Autolites to make the wires fit (the previous wires were the same type) and said it was all good :) I do need to pull the plugs out when I have more time to make sure the gapping is right. At Autozone I had wanted to buy the more expensive pre-gapped ones but the guy there said I should just buy the cheap autolites and he'd gap them for me. When I installed them it seemed to me that the gapping was strange but I didn't have a tool to check (I actually have gauges in my workshop that I use for my bandsaw but didn't think about it).

So, one less thing to worry about :)