Quoted from Shredder565:that is what it looked like. the third prong seemed to go to the others in some cases.
some people use these solder lugs on lamps:
https://pinside.com/pinball/forum/topic/voltan-escapes-cosmic-doom-restore-hep/page/5#post-1939831
https://pinside.com/pinball/forum/topic/medusa-playfield-swap#post-6269787