Coolant reservoir capacity on custom setup

[Ozz]

I will be putting in an electric fan setup soon and will want a stainless reservoir to replace the stocker. I also don't want to put in another plastic one to replace it.

I am looking at a few and am wondering how much capacity I will need in it. The sizes vary quite a bit.

I have a 92 5.0, intake, Vortech A trim, and that's about it for engine mods.