Kinda tight. Don't know the heat output of that thing, but just the interference from engine movement is NFG all by it self, even with the line removed.
Nothing can be done with that line & fitting that will accomplish much & worth the trouble
Raise the engine with a shim/plate/washers under the mounts or cut up the manifold, then a heat shield.
Rack on rubber mounts? remount it solid & lower.
