That tool might not be the right size. Its not for the lines on my 2000 which will be the same as the OP's. I got this.
Works like a charm. You gotta push in really firm.
Also DO NOT CUT THE LINE!
You also can just remove the entire fuel rail and injectors and just move it off to the side. Don't even have to disconnect.
You're going to be changing out your injectors anyway for the blower so you might as well just remove the rails and leave the line connected.
2000 Mustang GT Steeda #0048 34k miles. 99 Cobra 4V swapped, FTBR IRS swapped, exhaust, tuned by James Gordon.
Just because I give you advice, doesn't mean I know more than you. Its just means I've done more stupid ****.