i guess looking at the Cope site, the fittings for the lines at the trans should be 1/4" npt to whatever AN size you use.
I just ordered a derale stacked plate cooler from Mancini to hook up on my car since the rubber hose and clamps on the radiator trans cooler won't stop leaking...plus the existing steel lines rub on the everything...

probably just going to use some kind of flexible line or steel braided since moving steel tubing lines out of the way to pull the motor/trans seems annoying.