Whither the 1988 Buick Roadmaster?

So I may be obsessed with Neal Stephenson. Recently I was reminded of a line from his 1996 novel The Cobweb, written under the pseudonym Stephen Bury. It's a fun read, I recommend it. Anyway, the part I'm thinking about concerns a supposed 1988 Buick Roadmaster that the main character purchases (actually trades his wife's Japanese car for) based on its high "throw weight", supposedly an indicator of crash safety. All well and good. / Here's my beef: Buick did not put out a Roadmaster for 1988. The nearest model year Roadmaster would be 1991. In 1988 the nearest Buick equivalent would be the Electra Estate. Also, as far as I can tell, throw weight as a measurement has to do with ballistic missile payloads and not passenger vehicles. / Maybe I've got too much time on my hands, but it seemed worth a mention. Don't ask Neal Stephenson about it, 'cause he's not interested.