Ayuh,.... That looks pretty rusty, 'n I believe I see wear on the teeth,.....
Besides, odds are a new cable, 'n rack won't fit the old one,.....
To remove it, Take the nut on the wheel, 'n turn it out til it's dead flush with the shaft,.....
While puttin' extreme upward pressure against the wheel, Wack the nut with a BFHammer,.....
The wheel should Pop loose, allowin' you to remove the rest of the helm,....
