2000 GT Mustang Hard to start after sitting overnight
 

Hello..
I just started encountering starting problems with my 2000 GT Mustang.. Has 50k miles.
I added a new aftermarket fuel pump and filter @ 32,000 miles due to a clogged pump at the time and car would not start. This fixed that issue and has been running fine until now @ 50k miles.

Problem:
After the car has been sitting overnight or all day it takes about 5-6 cranks before it will start. I tried pumping the gas and it bogged and slightly back fired then started. But if I don't pump the gas it will start with no backfire just takes these extra cranks.
After it starts I notice no issues in driving. It idles fine, drives fine through all ranges and notice no issues.

Today I let it sit overnight and cranked it and it started at about 2-3 cranks. But before this problem it always started instantly on the 1st crank,
so I know there is some issue going on.

Can you please help me fix this issue...
I ordered a motorcraft fuel filter to try and bought a fuel pressure gauge today.
I will test this weekend. I heard that you need yellow teflon tape for the fittings on the fuel pressure gauge so I need to get that too.