Not converter bolts and no I can not make it do it consistently, this is part of the reason this has been such a pita to locate. The only time it seems to do it when idling is in the middle of traffic with a zillion cars around, never can make it happen in my driveway.

I drove it tonight and never heard it until I was almost home, after about 1/2 of driving.

Sometimes I'll hear it within a minute of leaving the house, no rhyme or reason as to when the sound appears.

As far as rockers, I have what ever rocker Indy sells for SR heads and a solid cam. it's not coming from the valvetrain, I can almost guarantee...