i am also restoring a RR shadow and had trouble changing the plugs , if you follow w the link i have provided this site is a brilliant sourse of information on virtually every made.
It has every bit of info you will need on any issue you have . just use the drop down menu to get to your car then the data you need .
It also has the full wiring diagrams and every thing .
i hope this not only helps you but anyone else who requires help.
RR bentley http://rrtechnical.info/.Technical
Service Documents (TSDs)
001 Pre-War Cars - This section is still available here, but will be phased out gradually
>>> Click Here to transfer to the Prewar Library on the Federal Website
002 Silver Wraith, Silver Dawn, Phantom IV, MkVI, R-Type & R-Type Continental 1946-1955
003 Silver Cloud, Bentley S-Series, Phantom V, Phantom VI & Derivatives 1955-1965
004 Silver Shadow, Bentley T-Series & SY Derivatives 1965-1980
005 Silver Spirit, Silver Spur, Bentley Mulsanne, Turbos, Continental R & SZ Derivatives 1980-2000
006 Millennium Series 1999 Onwards
007 Chassis Number, Modification & Production Booklets
008 Automatic Transmissions
100 Crewe'd Jottings - Periodical of the Victorian Branch Self-Help Technical Group - To Issue 30
101 O-Ring & Seal Materials Compatibility Chart - Brakes, Hydraulics, Engines, Transmissions, Cooling
102 Owners' & Drivers' Handbooks
103 Sales Material
104 Articles of General Interest & Subjects Applicable to All Models
105 Links to Technical References for Rolls-Royce & Bentley Motor Cars
106 Vehicle Identification Numbers & Codes
107 Technical Specifications
108 Production Lists and Modifications
109 1965-1989 Quick Reference Guide: Brake Parts, Exhausts, Filters, Hydraulics, Seals, Drive Belts & More !!!
110 Engine Settings & Tuning - All Postwar Vehicles 1946 to 1999 including Fuel Injection
111 Paint Codes - Rolls-Royce Codes, Colour Names & Cross-References
Miscellaneous and Videos
201 Videos & Galleries - mainly for entertainment
Originally Posted by rollmech
Originally Posted by James Carberry
My 72 shadow would not start in recent weeks. To cut a long story short I decided to remove and clean the spark plug. I found it a very difficult job and so far I have only got 5 out and cleaned. The car started and is running well howeve I want to get out the three remaining plugs under the brake fluid resivoir. Do I need a special plug spanner? On the other side of the engine I had to remove some pipes and parts which was not difficult. However on the other side where the brake fluid resivoir is I am not so sure about fiddling around as I am not a mechanic. Need some advice here.
What you need is a spark plug socket with universal joint attached then either a long extension or couple of extensions to go under brake fluid reservoir to get spark plugs out. make sure you start screwing new plugs in with your hands as you don't want to cross thread them. you may need to climb on engine to get your hand in on them. Personally I would fit new rather than cleaning.