It's possible that the PO installed this line into the head because there was no oil to the rocker arms. You may have more problems by removing it. It may be possible that the internal oil passages are plugged. This was a common problem for Ford "Y" blocks.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine