[wiswind]

The coil issue seems to be pretty common on the '01 time period.
If you put the new one in.....I would LEAVE it in.
Taking it back out is extra work....and extra handling of the spark plug wires.....extra chance to cause more problems.

Fuel filter is a routine maintenance item.......a restricted fuel filter puts an additional load onto the fuel pump.
Remember that the fuel system holds pressure for a long time......and even after releasing the pressure at the schaeder valve (using a rag to catch the fuel that sprays out)......you can STILL get a lot of fuel running out of the fuel filter connections.
For this reason.....make sure your face is not under or close to the filter when you remove the connectors from it.

IF you do the fuel pressure gauge idea......be VERY careful if you drive around with it.
It only takes a SMALL fuel leak to start a BIG fire.
The schraeder valve should be in the middle of the front fuel rail.....the rail that connects to the front 3 fuel injectors.

I would also look at your IMRC system.
It seems to be common on the '99 and newer to have the nylon clips break....and/or fall off leaving the IMRC shafts to flap about randomly.
THIS can also cause some of the driveability issues you are having.