You could but it may leak.
I would never reuse any gasket they are cheap and its just not worth the chance. It will probably not re seal
This question is incomplete but I will offer some thought. The transmission filter purchased from the local auto parts store has a rubber gasket attached to the tube which sticks into a port on the underside of the body of the transmission. The factory original rubber gasket tends to remain inside the port. I was told that the gasket on the replacement filter could be removed and the original gasket could remain in place to seal the replacement filter. The factory original gasket appears to be an aluminum ring overlaid with rubber and would likely require a special tool to remove. My experience with this situation is very limited and perhaps someone with better knowledge can give a more professional answer or offer advice for removing the factory original gasket. This is a completely separate issue from replacing the pan gasket.
You do not need to add a sealant to the gasket. Just make sure you torque the bolts to factory specs.
By replacing the whole gasket.
Yes there are sealers out there that can be used to seal or repair the gasket
One hour
Head gasket repair on a 2002 PT Cruiser requires extensive time, knowledge and tools. The intake manifold, cam shafts, and cylinder heads must be removed.
Replacing a head gasket is a rather lengthy process, much too long to try to detail in this space. I would suggest that you consult a factory service manual, Chilton or Haynes manual.
It requires replacing the head gasket.
It could, if the old gasket had failed.
Yes.
If you are using a new gasket, no.