Today I was getting my A15 powered wagon ready for summer by changing the oil and filter, as well as finally getting around to changing the cooling hoses, thermostat, and flushing the system.

Anyway, I realized that my oil drain pan had a bunch of metal on it when I was done changing the oil :( Appeared to be mostly coppery-looking metal, with some black-brown crusty chunks of metal mixed in as well
I noticed that theres a rattle when the car is running...at first I thought it was just a pipe or something clanging around under the car, but I'm pretty sure its in the engine. The engine is also puffing a bit of oil smoke, mostly when cold, but a tiny bit when warmed up as well. Other than this, the car seems to run just fine.

What does this sound like? I'm thinking that the main bearings are being chewed up. A friend thought it might have been the thrust bearing on the crank...I'm honestly not sure what it is. Help is appreciated!

well sounds to me like you need some bearings man...i had a similar problem with my b310.best advice i can give is get a new engine.it'll take less time to change your engine than to fix the old one plus it'll be cheaper too.

The drainplug has a copper washer, that's about the only copper in the whole car.

Rattling - probably heatshield on the exhaust manifold or the cat. My cat had a bad spot weld on the heat shield an it mad a terrible rattling. Maybe an exhaust hanger or something.

smoke might be valve stem seals or excess wear in the engine. I can tell you a completely rebuilt A15 is very reliable and doesn't use a lot of oil.