All Trucks, Campers, Trailers, RV's and Motor Homes - How to remove oil cooler lines

I have a 1998 motorchome on a Chevy P32 chassis with a 7.4 liter engine in it (although I believe the chassis is a 1997 model). One of the two oil cooler lines has begun to leak at both ends of the rubber hose portion, where the metal tube is crimped onto the rubber. I want to replace both lines. The problem is, I am not sure how to remove the lines from the engine. It is not entirely clear to me by looking at the connections, and I don't want to damage anything trying to figure it out. I have the service manuals for the chassis, but it just says "remove the lines from the engine", so I presume it is pretty straight forward.

Questions:
1) Can anyone tell me how to remove the lines from the engine. They are hex shaped where the metal tube enters the end-connector, with what looks like a hex nut between it and the engine. I have a photo but I can't figure out how to attach it to this post.
2) I get the impression from other posts on the web that the engine cooler lines are no longer available. Is that true, and if so, how do I go about getting replacements.

I would appreciate any help anyone may be able to offer.

Thanks.

Dave

Not sure about the connections but usually a good set of tubing wrenches is all you will need to remove lines, You can get lines made at a hydraulic Line supplier or a local parts store may know somebody who can make then up.

I am sure they will be like any other used today, you described the attachment having two hex surfaces prior to the engine. Turn one while holding the other with a wrench. It is important your wrenched fit properly so they wont damage the nut. You can also use two hammers, holding one at the rear side of the outer hex portion and striking the other side causing a quick distortion of the nut portion. That usually loosens even the most stuborn fittings. Be careful and accurate with your striking as you don't want to damage anything.
Bill

Thanks for the responses.

I'll give it a try and post my results.

Dave