Starter relay assembly [E3TZ-12A343-C / SW-1816-A] - NOS

[1986F150Six]

Excellent price with free shipping.

https://www.ebay.com/itm/234815098430?hash=item36ac120e3e:g:m2gAAOSwTYZjlLnx

[Gary Lewis]

That is the one for the diesels.  But, in spite of it saying New Old Stock it appears to have been installed since there's a screw head print on the base.  Still, at that price if it works...