I've got a set of mounts and the bolts, but I'm not sure what other hardware is needed and what the sequence is.

Click to view attachment

Install the mounts on top the body portion with M8 bolts, split-lock washers and nuts. Leave them slightly loose until everything is mounted so there's not tension from them being slightly out of alignment.

Slip in the M12 (?) bolt with a LARGE washer on top. Should look like this...

The top piece bolts to the mounts with 4 short bolts. The lower piece needs bolts to the engine case. Finally a pair of long bolts go through the mounts on the top piece, and then through the tubes welded to the lower piece. This hangs the engine from the rubber isolated sport mounts. Cant give you sizes, but i could if i was at the car.

So is that cup curved down?

I just used large flat washers ...

Usually, cupped washers on rubber bushings are cupped up, that picture is cupped down. I think cupped up is correct, but I don't think you'll notice a difference either way.

Cup up is how the factory did the 911 mounts.