1996 Ford F53 fuel line quick connects, what size ?

The fuel system is designed by Engineers who actually know what they’re doing. If your fuel pressure is low after you replace the fuel filter with a new one, there is something else wrong.

It could be a bad fuel pump, a clogged pump inlet filter, a crushed fuel line, or a faulty fuel pressure regulator allowing excessive fuel to flow back to the tank.

You should focus on finding the root cause of the problem before you fix it.