A few questions for guys that have used POR-15

[Yama-Bro]

I have my old 8.8 straight axle all cleaned up. I used a wire wheel to clean off the rust. It's cleaned to the point where it is down to the shiny metal. I was planning on buying POR-15 to coat it. I have a few questions for those of you that have used POR-15 it before:

1. Will the POR-15 adhere ok with most of the rust being cleaned off?
2. Did you use only the POR-15 rust preventive coating or did you use the whole system, degreaser and metal prep?
3. How much do you suggest buying to cover an axle?
4. Top coat or not to top coat? Can I use a cheaper rattle can paint?
5. Is there another product better suited for this?

Thanks again!