well darn, there's a size limit per thread, so i can't attach the before and after pics. instead, here are some links:
next up, i decided i'd buy new saddles and do a better job of slotting. i asked heritage what model bridge was on the guitar, and the response i got was "TonePros System II". unfortunately, there are multiple nashville bridges in the System II family, so i wasn't sure if the bridge was a NVR2 or a TP6 or something else. i didn't follow-up with heritage on that.
due to the ambiguity of the bridge, the graph tech folks were unable to recommend a definitive saddle replacement (http://www.graphtech.com/products/brands/string-saver/string-saver-originals-tune-o-matics). i ended up ordering the Allparts BP-0305-010 Chrome Saddles for $20 + shipping.
the good news is that these saddles fit into the bridge using the existing intonation screws. the bad news is that these saddles were a bit shorter than the original saddles. unfortunately, that meant i'd have to tweak the bridge and the tailpiece height up a bit.
i slotted the new saddles with off center grooves. as i'm an amateur at this stuff, the job looks amateur again - i missed the mark on 1 or 2 of the saddles! i'll leave things as is. eventually i may buy another set of saddles (practice makes perfect, right?!)