B-HNL is indeed the ex-Boeing 777 owned by Boeing, the one you see in all the magazines and books in Boeing house colours. Serial 27116, Line no. 1.
B-HNC was indeed the first 777 delivered to Cathay, but was newer than B-HNA and B-HNB, these aircraft being used for test and certification purposes. B-HNC was not used, as far as I know, so was delivered soon after roll-out, whereas HNA and HNB has to be retrofitted and cleaned up before delivery.
Hope this answers your question.
[This message has been edited by geh065 (edited 21 December 2000).]