[V8 Bob]

IMO, the most important ground is from battery to the engine, usually at the bell housing, or lower front of a flathead block. I would not use one of the stater bolts because of it's small size and low torque capacity.
Grounds from the engine to the frame and body can then originate from the main engine ground, but can be smaller diameter because of much lower current loads. Using this method keeps the grounds as close as possible to actual battery ground potential.