Head Gaskets are "relatively" Minor. This means that for the production numbers the cars have experienced, the number of HG failures are somewhat insignificant.
Not all Northstar V8s will blow their head gaskets. You have to keep in mind that a vast majority of people come to the forums to complain or seek help for a problem. There are few that praise their cars. THer is, however, one dude over in the Northstar forum with 540,000 miles on his BONE STOCK Northstar.
It's up to you on whether to ditch the Eldo or not. Would you consider a $3,000 repair on a car worth roughly that much worthwhile?
How much do you like this car?
Has the car ever been overheated?
What are the service records?
It seems, to me, that repeated overheating of the Northstar is a BIG part of the failure. Head gaskets almost never fail on these cars, it seems that the headbolts lose their clamping force, and BOOM. HG "failure". It's a bit of the 'Chicken or the egg' with HG failure, though, as general consensus is.
If it's never been overheated, and serviced regularly, that VASTLY improves your chances. If you plan on keeping the car, change the coolant yesterday, read up on the technical archive, keep it from overheating, and ENJOY!
Oh, and if you decide to sell it, post a listing on the classifieds. I'm sure there are some members
that would LOVE a crack at this car.