How do you change a spindle on boat trailer?

To change a spindle on a boat trailer, first, ensure the trailer is secure and raise it with a jack. Remove the wheel and brake assembly, then detach the old spindle by cutting or removing any bolts or retaining rings. Install the new spindle by securing it in place, reattach the brake assembly and wheel, and make sure everything is properly aligned before lowering the trailer. Finally, check for any play in the spindle and ensure all components are tightened correctly.