Re: 2 days ago, only 1 cylinder firing, yesterday BOTH, today just 1 again.

I can tell you from a good amount of experience that the Autolite AP63 Platinum plugs do make a difference in the Virago's.
Since the problem moved with your coils, have you gone through the procedure to check out the coil primary and secondary winding? There is a procedure in the Clymer's Manual for testing them with a Volt/Ohmeter. Another possibility with the older Virago's is the coil wires. They have a resistor in the end of them of about 5000 ohms, sometimes taking it apart and cleaning it inside can help. If your bike has the replaceable wires, then replace the wires with solid copper 8MM automotive wires. If not, try ebay for some used coils. Also, I have a source which might have some coils off an '86 XV700. Try Mark's Cycle Store in Grass Valley, CA. 530-273-8337. If he doesn't have them off the bike he has, he can probably find them for you.