I'm putting 6x16 Fuchs on my 73 914, its a 2.4 six conversion. Probably 205x55x16 tires. Yes, they will fit.
I'm not going to race, I'm probably not going to autox, and if I do I don't care about having the best autox tires. I want tires that do as many of these as possible:
don't make a lot of tire noise
provide a reasonably comfortable ride
don't squirm too much on the bay area's grooved paving
work good in the dry and the wet.
What are you driving on that you are happy with?