Design page. At the top middle-ish is your boil time. You can just highlight it and change it to 90 minutes. To change your hop times from 90 minutes to 60 minutes, you double click on each hop in the recipe on the design page. It will bring up a window where you can change it.
The thing is, it's going to be a really sweet tasting beer. Too sweet, I would think. Those changes will affect the bitterness level slightly, but not enough to balance the sweet to bitter of the recipe. It's way strong for an Irish Red Ale.
It is a very simple recipe though, however, I'm not sure it will be the most enjoyable drinking beer. I'm thinking it will be very sweet and very boozy.