put cylinder 1 on tdc, pull out the cas and you will see some markings on them... the tab will have a punch mark on it, and the outer base on the cas will have a mark on it, make sure they line up and that will confirm that the cas is on right..
i've never experiences a cas that was out 180 degrees on a stock ecu, only on a wolf.. it seemed to work okay but thats only because the wolf doesn't run sequential, whereas the stock ecu supposably runs seq inj and waste spark...
worth a shot mate, see how you go..