Blown Head Gasket 94 EX

I have a 94 Civic EX with what I'm pretty sure is a blown head gasket. My son called me and said his car had overheated. I'm not sure how far he drove it hot, but the radiator is full of oil. It has been sitting outside for 2 months or so like that. I'm just now thinking of tackling the job, but I'm not sure when I can get to it. Should I go ahead and flush the system? Is there any point after sitting this long? What are your thoughts?

you'll need a radiator shop to flush it for you, and the heater core.