Use remarks to cross reference attachment points between the core and jacket piping on the isometric.
You can place remarks by setting the Locate Filter to Piping Parts, selecting the part that you want to remark, and then selecting Insert > Note. You can also use the Notes tab on the part's property dialog box.
In some cases, you can use the component number to trigger a special detail on the isometric drawing. For example, if there is more than one way to close the end of a jacket pipe, the end component can carry a component number of CL-1, CL-2, CL-3, and so forth. This in turn can trigger the correct detail for the corresponding closure type to the isometric drawing.