Keith:
My thoughts for what their worth (0.2 cents)
My '76 Targa has 163,xxx miles on the 2.7 and it was "done" (time certs, head studs, valve stems, reseal case, etc... back around 60,xxx miles [many, MANY moons ago]. Car doesn't smoke and has very few leaks (oil return tubes are the culprit I think). Once I went through CIS several yers ago it has been reliable as a rock. Albeit...not a very fast rock.
These much maligned
middle year 911s are good cars ['76 on with galvanized bodies] and can always receive a transplant 3.0 or 3.2 in the future. My reserve plan is from the remains of a '74 targa I picked up that had a CIS 2.7 with euro P&C, 964 grind cams, etc...
Bonus is that they really are easy to work on.
Jason
P.S. One can NEVER have enough P-cars.