That is exactly the reason I ended up finding this site, I turned the nut off and dropped that stupid thing into the pan. After 2 days of trying to fish it out while laying in a street full of wet snow I cut a hole in the side of the pan and repaired it with a sheet metal patch, screws and sealer. I do NOT recommend this. I eventually had it welded when I pulled the motor. If I had to do that again I would drill a round hole and plug it with an expanding rubber bung as suggested by another forum member after the fact.
You can easily replace the gasket.
Remove the dipstick tube from the tube holder. Be carefull not to lose or damge the small o-ring that seals this assembly.
Run a piece of coat hanger or similar with a u bend on the end of it just small enough to fit through the hole and then pull it back so it catches the inside of the part and you have something to keep that internal piece from falling in.
Remove the outer nut and lower the inner piece enought to pull off and remove the old gasket.
Clean off the inside sealing area, install new gasket, pull the inner part into position and reinstall the outer nut.
You can then pull hard on the wire and it will unbend and pull out.
Use a short enough wire that you can slide the gaskets over it to remove and install them.
Removing the wheel and starter will give you more room to work.
