There was some discussion on the process for trashing cards as the Corp. The question has to do with the rule on page 13 which is quoted below.
"When installing a card in a server, the Corporation can first trash any cards already installed in that server. Trashed cards go to Archives faceup if they are rezzed, and facedown if they are unrezzed."
The question is this: if the Corp installs a card to a server, can they only trash a single card in order to replace it with another or in the case of ice, trash a number of ice in order to bring the cost down OR can the Corp trash any of the cards in that server they want?
Here is an example situation: A server has 1 Agenda, 1 Upgrade, 2 Pieces of Ice.
The Corp wants to install an Asset to that server and also trash all the other installed cards. Are they allowed to trash all 4 cards so that only the Asset remains or can they only trash the Agenda in order to replace it with the Asset?
I think the rulebook clearly states that all the cards can be trashed. It doesn't state anywhere that the trashing is limited to the card type you are replacing.
Is there an official ruling? Thanks.