Nice info, Otto! :D My 81' FLG90 has sheilded cavities and black PIO caps. My Early 80'S RLG-90 and RSG-75 AY, both have the sheilded cavities and grey PIO caps. All my other 80's Burny's, have the green polyester caps except, My 94' RLG-70, which has yellow caps, a thicker neck than all my...