Hayley timing question

By Rain King, in Android: Netrunner Rules Questions

We had a strange situation come up tonight that I think we ruled correctly but I wanted to confirm.

My opponent was playing Hayley Kaplan, which reads "The first time you install a card each turn, you may install another card of the same type from your grip (paying it's install cost)." She had two free MU and installed a Cache, putting the three tokens on it. Here's where it got tricky.

She wanted to trigger Hayley to install a Self-modifying Code, trashing the Cache to make room for it. Would she have the opportunity to use the paid ability on Cache to remove the tokens for credits before installing the SMC? We decided that it would not in fact work because Hayley's ability happens immediately after the first install and there would not be a paid ability window between them since it is not actually a second action. Is this correct?

You are correct, and for the reason you think you are.

Thanks. ^_^