yep that's the engine... but the 2nd generation one, which has the modifications done to it.. (I hope !) actually I bought 2 wagons but on the way back (400miles) the older one blew a head gasket (typical), but it was a 1980 model with the 1st generation diesel. We kind of have a few of those olds here , I should get a goodwrench engine (to be rebuilt ) soon , just in case. We do some modification on the fuel supply lines here in order to get over the common problem you guys had with bad diesel gas, actually we put Peugeot filtering systems. Here most cars are diesel, that's why here it stinks, and it's noisy. I'm not that happy with that diesel (I swore that I would never have a diesel!!) , but it's a lot cheaper to run , and I'm working on it in order to make it reliable. Also it's my wife's daily driver (.. so technicaly , I'm not driving a diesel...honor is safe!) , and she doesn't put much miles on it......
If you have access to E-Bay, you can find AM/FM casette decks pretty often, try to search Ac-Delco casette to find them.
This site gives you a list of radios for Olds-mobubbles too. Most of them come from EBay ads, but some are from other sites: http://vehicle-db.com/parts/search.pl?part=Olds+Radio You could refine the search terms.