all right. first off, thanks for all the help so far!

the car now has a "fixed" cat and patched exhaust hole, then seafoam run through it twice, then new plugs, couple of oil changes (one right away, one after the seafoam), and new front rotors and pads (rears are on order, fluid still needs flushed). runs smoother and revs faster. the brakes seem to "bite" less than they used to, but ill wait a couple hundred miles for them to bed-in...

the flex disks look solid, and even a bit cleaner than the rest of the car, so i think they might be new-ish. the engine doesn't bounce MUCH when shifted around. one "jump" as it starts, and thats it, minor "hop" when shifting. the clunk occurs most when shifting from D to P and vice versa, but also mildly when moving and lifting off or getting on the gas, definitly form the back... rear subframe mounts?

the mild intermittent clattering, i assume, is the belt tensioner and/or shock. the tensioner vibrates a lot when the engine is running, and pressing on it with something cuts the rattle in half or less. new tensioner shock?