1969 977K loader hydraulic hardline (underfloor,leading to vertical pipe and swivel union) has a flat area in it,my engine throttle rod lays right on this area of the tube; I'm not sure if the flat area on the hardline tube is designed that way for clearance or has the throttle rod worn its way into the tube? I've checked with some used parts suppliers and they say all thier old lines on the shelf have the flat spot,but they are in different areas..any info or experience out there on this possible problem??

I think you should repair the throttle cross shaft bushings, rod ends and pins to get rod up off of the line. Then braze a patch over the worn spot.
Later Bob

yup did some brazing magic to repair the line;filled the worn spot in with braze and capped it with a section cut from an old hardline with more brazing.I thought from my original question that maybe Cat had flattened this area in the hardline for clearance with the throttle rod..after looking at the line I'm sure now it was just 37yrs of use. I wrapped a section of rubber hose over the throttle shaft to prevent this again in the future.The throttle rod hangs down a bit against the hardline due to it's length..Bushings and rod ends all OK.