Do I need any gaskets or fasteners to install this?

The manifold itself is included. You'll need exhaust gaskets and stainless bolts to secure it to the cylinder head and turbo flange — source those separately based on your turbo kit's specifications.

Will this work with any T25 turbo, or are there compatibility limits?

T25 flange pattern is universal, so it bolts any T25 turbo. Your limiting factor is engine bay clearance and oil/coolant line routing — verify fitment with your specific turbo kit before ordering.

Does this need ceramic coating or paint before installation?

Stainless steel doesn't rust bare, but ceramic coating reduces under-hood heat and extends manifold life under sustained boost. Paint or coating is optional — the manifold will function without it.