In 1995-96 have a vented optispark (distributor) that is right below the water pump so when the pump starts leaking through the weep valve there is a chance that the optispark will crap out but because its vented the chance is reduced.
The coolant level sensor (40 bucks) goes out after 55k miles
The Water pumps last 55-70k miles on average
93-97 drive shafts are not usually balanced so check for car vibrations at speeds of 70+ mph


98+ LS1's have had cases of piston slap

No real problems with these cars. Just general wear.
97 and below are cheaper to mod
98 and up your modding is more expensive but gains are better