How much sailing experience do you have? doing it by yourself? If its just you and you have not much experience I wouldn't. Across the bottom of Yorks from Innes to Edithberg can get pretty rough and windy. Its also a lot further than you think. someone I know recently did Whyalla to Adelaide and took them nearly 3 full days ( just sailing during daylight hours, they didn't have great winds)
Cripes, sorry but that is a bridge way way too far for a Hood20.............suggest take the mast off, crane it out of the water and put it on a truck and road it to Adelaide, crane it off and re-float it then re-install the mast. I am aware that around 20ft boats have sailed around the world..............they with very extensive prior planing and hulls and rigs built like brick outhouses.............how old is the Hood 20? how old is the standing rigging?
r13 that is also a good point I should have mentioned. Doing a long trip like that on a boat you aren't familiar with is not a good idea. Especially when you are not familiar with systems and unsure of reliability. If something critical breaks you really are at the mercy of the waters.