OK, it's time for new alloys for my 1987 Coupe GT. I'm think of getting 15" or 16". Anyone know what the proper offset and bolt pattern are? The standard tire size is 185/60/14. So, by my calculation, the right size for 15" would be 215/45/15, right? This would only be .5% off from original specs. For 16" it would be 215/40/16, right? .1% off. What are your thoughts? Advice please!

Plus 1:
195/50-15 or 205/50-15
Plus 2:
205/45-16 or 215/40-16

Pick relatively common sizes to make sure you'll can buy replacements down the road. ET45-ET35 is probably good too.