OEM heater

[Erics51chevy]

I am using the original heater and am worried about the two 5/8 water connections going to it. They seem like thin metal tubing without a dimple around the edge like a normal water connection. I have an LS under the hood and have already had a coupler blow off and shoot hot water everywhere. The last thing i would want to do is burn my passenger.

Was the water pump psi less in a 235 then the ls motors?

Im thinking epoxy might be in order so i dont crush the tubing with a hose clamp.