I have been told that the 98 GT already has the correct heater tube nipple as well as the correct coolant hose (Hcore to block). Is this correct for the PI intake swap?
When I installed a PI intake on my 97GT, I didn't have any trouble with the heater hoses. One of them I had to reroute or cut slightly to fit nicer, but it really wasn't a big deal. Keep in mind... replacing water hoses on a 13 year old car isn't a bad idea anyway. They tend to rot or get hard and brittle over time and could leave you stranded one day. Might as well replace them while everything is apart.