idle speed miss

I just replaced the oil and spark plugs in my coupe. Ever since then it has been idling a little rough. Over I am guessing 1500rpm, it is smooth as cream. Any ideas? I put in Autolite #69 plugs. Did I put in the wrong plugs? Should I pull them and put some NGK's back into it?

Thanks.

Made a mistake. Spark plugs are actually #64s. I just check them all.

There is a Technical Service Bulletin on this problem:

http://img30.imageshack.us/img30/7540/sliceq.jpg