They are all plastic
Little trick here is to check the ground strap.
There should be a short strap that goes under the blower housing rear bolt, between the crank case & the plastic blower housing
These tend to get dislodged when the blower housing is removed if you take the bolt right out in place of just backing it off till the housing clears the bolt head .
I like to make a new one hat runs from the starter motor mount to the rectifier as starters are not removed any where near as often
The straps seem to hole up well but I have found a couple where the wire had broken at the crimp.
This usually cause excessive heat so the terminal melts into the blower housing .