Ticking noise, 383, can't locate the source

Have you looked closely at the valve springs themselves for a broken one? Remember, don't assume "good" because it's "new". If you find nothing, I think would see about upgrading the rockers. They were not made for that size camshaft.......even though it is a mild one. They need upgrading anyway, whether that'll solve the tick, I guess you can keep your fingers crossed.