LAPD SWAT has used 1911 type handguns since it's inception and just went to Kimbers several years ago.
I'm not sure that that's true. I've seen the report of the SLA shoot-out in 1974 and none of the itemized SWAT weapons and ammunition were of .45 caliber. It also stated that each SWAT member was equipped with a .38.
I do recall noticing an LAPD SWAT member utilizing a .45 gov't model in a news feed in the early 80's or perhaps late 70's, so they did have them by then.