Touching Up/Refinishing 870 on a Budget…

I have a 2004 870 Express Tactica@ (6+1), that I'm upgrading to the Magpul Stock & Pump and a side saddle w/ picrail.

BUT the finish is so-so, with multiple scratches and spots where bare metal is showing... thinking of either just touching up or refinishing the receiver and other steel parts with Brownell's Aluma-Hyde in black matte.

Thoughts or experience with this?