2000 turns right "off itself" onto Pauinako St to End at at Kaumana Dr (former 200) and 200 takes over. The whole routing of 2000 really is so stupid as they took it to a point where they intended to make it a 4-lane at Kohomana St in Hilo but then ended the split road there and turned 2000 onto the cross street with poor lane management and turned it onto Puainako St through residential and school zones with out any fanfare. I was dumbfounded by it when I visited last month that the route was not completed, but I guess it's so much of a usual HDOT action taken. All those container trucks from Kona seem forced onto old Saddle Road and Kaumana Drive to get back to the port to refill. (they end up taking many narrow highways (190, Waikola Road, Old Saddle, etc) and put many residential Hilo neighborhoods in danger (IMO) because 11 and 19 are not safe routes for semi trucks (for a lack of a better term given it's on islands and they only transport containers between Kona and Hilo.
Definitely a messy situation. Hawaii DOT had plans to straighten HI 2000. But this fell by the wayside, after the Governor ordered the DOT to make only minor improvements to maintain the existing network, with a few exceptions for major projects such as extending HI 200 from HI 190 to HI 19.
The need for truckers to haul containers cross-island, from Hilo to Kailua-Kona via the FUBAR'd Hilo highway network, is in part that Kailua-Kona doesn't have a deep-draft harbor, just a small boat harbor. Kawaihae, north of Kailua-Kona via HI 19 and HI 270, has a deep-draft harbor, the only one on the Big Island other than Hilo's. I don't know why the container ship operators don't make greater use of the Kawaihae harbor, maybe the operators prefer to centralize their operations in Hilo, and think the Big Island is not populous enough (about 200K population) to support two container ports.