mounting 64 wheels and tires on a 71

We are going to carlisle and will be driving our 71 from ontario. she has p225 70r 15 tires mounted on original rims. The spare is an original f70 15 of which i prefer not to use. We have a 64 with p205 70r 15 tires again on original 64 rims. Could we use the 64 spare if required on the 71 without complications
thx for any help

My first thought would be to check the bolt pattern to make sure they're the same. The size of the tires shouldn't be that different but I'd still only use the '64 spare on a front corner. If one of the rear corners goes flat on you, first put the spare on a front corner, then put the tire just removed where the flat is. That way you'll have like tires on the rear corners and won't run the risk of putting any extra strain on the differential. And then be easy on the brakes as you might get a pull with the dissimilar tires up front, especially if you stomp on them.

Thx norsky for the tip. I'm going out to try a switch of wheels tonite.
Thx Ralph

Jim's always got the right answer! (But hopefully you'll get the '71 there in one piece without a need for a spare.)