You have to replace the whole line. It passes through the block and attaches to the oil galley on the other side. If I remember correctly, the line goes through the water jacket, so drain the cooling system before you loosen the block fittings. And use tubing wrenches. I suppose you could use a coupler of some kind if you can find one of the proper size- hardware store item maybe, or a parts house that deals with the service trade, rather than the consumer market; NAPA would be a good place to look- but don't tell the counter man what the vehicle is- he'll first say they don't have parts. Just take the broken fitting for size. Its a compression fitting, so something should be available. The risk with adding a coupler in that line is that there is no support for the line between the block and the rocker arm connection, and the extra weight on the line may cause fatigue and break it again.
If the engine has been run long without oil to the rocker arms, the rocker arm bushings and the shafts may be badly worn. They wear enough even with oil up there, but that was a common problem with those engines. Parts are fairly readily available, but fairly costly for the whole assembly. It may be possible to re-bush the rocker arms; in the past, no one bothered with that- new arms and shafts were the order of the day. I don't know if anyone at this site has tried re-bushing the arms, but that would be worth looking into. Maybe someone else can add insight to that.
Good luck with the job.
Harvester
