In reply to wild_nomad:
If you haven't been before the BMC parking spots are on the left (driving from Tremadog village) immediately after you pass Eric's campsite/cafe(which would be on the right). They are right below the crag. There is space for four/five cars parked carefully, this has been overflowing onto the grass verge under the trees recently.
For upper tier (Pant Ifan) you park outside of the old industrial yard when leaving Tremadog village (there its lots of parking here, just don't park in front of the gates).
Post edited at 16:38