Actually, I was kinda baffled by the original question because it seems to assume all electric guitars are strung 6-a-side...
Not while Leo owned Fender, but CBS-Fender departed from the original, standard Stratocaster bridge & trem design for the first time in 1980 when it introduced the first 'factory hot-rodded' model, The STRAT. Although still a 6-pivot system with the option to use as many as 5 springs under the hood, the bridge saddles and trem block on this model were cast of heavy brass for producing radically more sustain than ever:
This guitar was worked
hard for 5 years, and the saddles show it, but unlike most of today's today's import or USA guitar 'gold finished' hardware, the gold held up because it's coated in 22K 100-micron gold electroplate. BTW: the pup polepieces, pg screws, trem arm (except for the cap) and the tuners were never gold on this guitar. It's one of the earliest-made from '80-'81 , rushed to market before all the gold parts were ready.
A tinkerer til the day he died, Leo ultimately outdid his original 6-pivot design himself when he came up with the
G&L Dual Fulcrum Vibrato.