It did, the Mineola Blvd. bridge was replaced, Nassau Interlocking which was East of the Herricks Road crossing was also eliminated, the switches where the Oyster Bay diverts North were replaced, and like I said before a new interlocking was constructed West of Carle Place right around the bridge that goes over the Meadowbrook Pkwy. and the bridge that goes over Glen Cove Rd. I don't know what the name of that interlocking is though, and I don't know the name of the one in between New Hyde Park and Merillon Avenue.
As far as the pre-elimination of Herricks Road, thank for confirming that the whole time when it was a four-lane crossing it had dual-planked gates, and it was actually one of the last to have those. From one photo taken in 1961 with a Kellogg's billboard, the crossing was two signals with the Southern signal having the warning bell and the Northern lacking one with really long gates that only covered the two lanes next to it with two puny pedestrian gates on the opposing side, which left a very wide gap two lanes wide. No wonder it was hazardous, you could make a straight line through it. I'm really surprised that in the 1970's they didn't install overhead flashing lights like at Stewart Ave. in Bethpage, or New Hyde Park Rd.
This is the train to (NYC). Stopping at: Babylon, Lindenhurst, Copiague, Amityville, Massapequa Park, Massapequa, Seaford, Wantagh, Bellmore, Merrick, Freeport, Baldwin, Rockville Centre, Lynbrook, Valley Stream, Jamaica, Kew Gardens, Forest Hills, Woodside, Penn Station OR Grand Central.