Need help confirming bad head gasket.
I have a used 2003 G35 coupe 230k miles with overheating issues and cylinder 3 misfire.

I replaced a busted hose on the oil cooler, and replaced the thermostat housing. The old thermostat had been cut out.
I replaced cylinder 3 ignition coil with Hitachi IGC0007, it was aftermarket and looked cheap, the others look stock.
I replaced spark plugs and valve cover gaskets, cleaned the plenum and throttle body, and swapped injectors 1 and 3 while I was in there.

After reassembly, the car runs a little better but still overheats. There was white smoke coming out of the exhaust but it stopped after a few minutes.

With the pressure tester I find a leak near the water pump at the back of the timing cover area, So I'm planning on doing the water pump at least and possibly also timing components if I need to do the head gaskets. . The front clip is already removed minus the radiator. I can't confirm if the head gaskets are bad and am wondering If i should just do the timing kit and head gasket or try to just do the water pump and see what happens.

Symptoms of possible head gasket failure:

White smoke from exhaust (went away mostly)
Heavy milky residue inside thermostat housing
oil in coolant?
Bubbling coolant reservoir
Overheating quickly

However

Engine passed block test
Oil level never changes, doesn't look milky or contaminated
I took spark plugs out and pressurized radiator, I'm not seeing any coolant in the cylinders after 30 minutes. Just water dripping out of assumed water pump,

Compression test (cold) seemed OK
1 - 160
2 - 150
3 - 160
4 - 159
5 - 155
6 - 157

Do you think the Head gasket is bad and is there anything else I can do to confirm before doing the work? Or can this be caused by a bad water pump and/or radiator?

Also, is this much metal normal for a camshaft position sensor that's never been removed?

Thermostat Housing

Oil in coolant?

Bad or Normal?

 

There's a hole near the timing cover that allows coolant to drip when the water pump goes. That's probably where you're seeing the dripping, which would be a good indication that it needs to be replaced. It's possible that you're experiencing over heating from a faulty water pump and also from air in the system due to it leaking. I would replace the water pump and thermostat with OEM and burp the system really well.

While you're doing that, pick up a combustion leak detector. They're relatively cheap and can help determine if it's a blown head gasket or not.

 

I used a friend's block tester for about 20 minutes but the fluid never turned yellow. I might just do the water pump and try the test again afterward and purge the air really good like you suggested. Thanks I didn't know about the hole for the water pump either.