thermorex is correct,
as Pap explained in his write up, the big return line from the back of the CP3 injection pump over to the four way connector has a hard plastic inner liner. So, if going to a brass setup, you will need to replace this hose with a good quality marine grade fuel line and some good fuel injection hose type band clamps...

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Supporting Vendor and Moderator of LOST05 Jeep Liberty CRD Limited 
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