Not my favorite year for Riviera. The all-new one (FWD) GM was preparing (along with a new Eldo and Toronado) got delayed a year, so to keep the nameplate alive, Buick basically dolled up a LeSabre coupe into a 'Riviera' for 1978.
The styling is not too distinctive, especially compared to what was coming in '79. But these are very comfortable and long-lived highway cruisers.
It does seem like a steel for that car, what 400 engine was used in them? I suspect an Olds 403? It does have the sport steering wheel, I wonder if it has the Sport Suspension? If it does they were pretty good handling cars also, just not very distinctive in 77 & 78.
