With 8 hr endurance it's virtually impossible. You could go up through Russia, the Aleutian islands and then into Alaska, but you'd need clearance from Russian authorities and it would be a hassle. But doable - it's been done.
If you go via Hawaii you have to go through Micronesia and probably Pago Pago. But at some point you will have to go from Hawaii to San Francisco in one hop and it's 1500nm without a single piece of land in between, so you'd need a ferry tank for that leg.
Antarctica has no GA airports or facilities as far as I know. You could perhaps get permission to land at one of the various scientific or military airstrips, but to get 100LL fuel there, you'd have to ship it in beforehand.
The Pacific is a pretty unfriendly stretch compared to the North Atlantic where the longest leg - if you really want it to be - can be as short as 300-400nm. But certainly people fly it all the time - every delivery of an old or new aircraft to Australia/NZ take this route.