I know you have a new fuel filter on the car but when you remove the old injectors, look in the top to see if there's any crud there. One of those sites we looked at suggested to always replace the fuel filter any time new injectors were installed. If there's crud there, I'd change the filter again.
When we replaced the injectors in the Fastback Formula, the tops of several injectors were totally plugged even though the car got a new filter.