[dougfamous]

Just take scrap lineset and braze on service ports. Flare the ends and connect. I have a set in the truck I made years ago they come in handy sometimes.

What he said ^^^

Take some scrap copper and flare one end to attach to the head.
On the other end braze on schraeder taps (at the supply house we call them "tube extensions") (like this: https://www.jbind.com/product/copper-tube-extension-single-step-5/).
Attach them to head.

WARNING: When pressure testing be sure to stay below the maximum test pressure on the unit tag or you risk popping it like an expensive balloon

When done save them for future use.