York County garages eager to replace your Buick engine

I don’t think that today we usually replace any major components of our automobiles unless they fail, so I was surprised by a prominent ad in the March 25, 1948 Gazette and Daily pointing out the advantages of replacing the engine in your Buick with a new one.
The local garages who banded together to place the ad were Miller Buick, 229 South George St., York; Grimm’s Garage, West Broadway, Red Lion and J.T. Amberman, South Main St., Stewartstown.
They would be happy to put the “…brand-new straight-from-the-production-line Fireball engine in any Buick from 1937 models on up.” World War II had ended less than three years before, and I’m guessing that automakers were still trying to catch up on automobile production. Virtually no consumer cars were manufactured during the war years, as the makers had all converted to war production.
The Buick motor plant must have been producing well in 1948. In fact the ad explains “WHY WE CAN MAKE THIS OFFER: Out of the Buick plant engine productions is going great guns. It’s stepping along faster than complete car output. So we have these brand-new engines ready to put in your car right now.”
“Pop and snap” were promised to come back, as well as better gas mileage and less oil consumption with your new motor. Driving would be most responsive, comfortable, dependable and fun. Current technology in the 1948 ignition system, carburetor, air cleaner and clutch were extolled.
The cost of the new engine wasn’t quoted, but the prospective customer was assured it was “…a Price You’ll hardly Believe.” Buick owners were invited to: “Come in and talk it over.”
I don’t know a lot about automobiles, so was/is replacing a still running motor done, or was this an innovative marketing campaign by Buick to avoid having to shut down or slow down motor production until the car production caught up? The only time I replaced a car engine was after an unfortunate encounter with standing water after an intense rain storm a few years ago.
Google maps presently puts George Beauty Supply/Golden Beauty Supply at the site of Miller Buick, on the northeast corner of George Street and Hope Avenue. It could possibly be the same building, as car dealerships took up much less space than they do now.