What do i have?

When you say, "truck" do you mean 1/2T ish through 1T ish? I see nothing here that smells "heavy truck." They made both SBM and RB engines in usually called -3 (dash 3) that could be quite oddball, and typically used the large 18mm tapered seat Ford style plugs

Some industrial engines used 8 bolt cranks, instead of 6 commonly found in cars and light trucks