I did find in the orignal parts book a listing for a 58-59 "main cylinder pipe adapter" pn 3739974 which might be what I need to find. I don't see anything on the usual parts suppliers websites for any special fittings for the 58/59 though...
Michael
I agree that 3739974 looks like it may be the right part.
The first picture that EdPruss posted, looks like the female end of inverted flare. If all you need to do is get a single 1/4” tubing line adapted to the master, take the master with you (if you can), go to NAPA or another FLAPS and see if they can match it up.
