Personally I’d avoid using wheel spacers.
For safety’s sake buy some wider or different offset wheels and do it the right way.
15x7” Rally II wheels with 275/60s fill up the wells pretty nicely and really don’t look too small or need to be spaced outward, here’s a ‘70 Tempest as an example:
https://forums.maxperformanceinc.com...15&postcount=5