Remove drain plug, Cessna Part Number MS20913-10 or MS20913-ID, from the fuel selector valve, and replace with CAV-110D (MT-1077) or CAV-110H-4D (CM-1077) (See page 3 for model serial numbers.) View PDF on drs.faa.gov ↗

The STC PDF is authoritative: installation instructions, ICA requirements and limitations.