I dunno, might not be a problem. There were definitely threads showing on my lines before I removed them. It may not have been half the fitting but probably easily 1/4-1/3.
If you can't see any problem with the threads on the fitting where it stops I'd say it's probably ok.
But as LG mentioned, make sure it's the correct type of fitting and that the parts monkey didn't give you a SAE flare line when you needed a metric o-ring or vice versa.
'84 CJ-17: 17" stretch, locked Toy axles, 5.5" lift, FI, AX15, D300 w/twin sticks, boatsides & junk.