From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Drilling for main cylinder and end cover, common to 20/25 HP & Phantom II models.
| Identifier | ExFiles\Box 16\5\ Scan034 | |
| Date | 13th November 1931 | |
| FS{F. Steele}3922 DOTTED LINES INDICATE PRESENT DAMPER CASING OUTLINE DRILL .337 DIA TAP .375 DIA 26 TPI RH{R. Hollingworth} E.77242 F.83919 F.83920 F.77983 E.81513 .625 .4375 REMOVED... HEIGHTS... RESERVED... DRILLING FOR MAIN CYLINDER & END COVER COMMON TO 20/25 HP & P.II C&S DEPT 13 NOV 31 DERBY SCALE 2/1 WH | ||