Here is an enhanced version of your picture with corrected colour cast and a little additional lightning.

- IMG_7688_zpsknez6yah.jpg (112.06 KiB) Viewed 1939 times
The Silver-Grey model is a fairly hard to find version, it looks like the original model issued in 1966, but is actually the later 1970 issue, using castings from the 'Hardy Boys' Rolls-Royce. The other Two are re-issues from 1985-86, can't pin them down further as both mascots are missing but essentially the Mascot was modified during this period and on the very last issues in 1986, the chassis was also modified.
Nice trio of Rolls-Royce models to have in a collection.
GHOSTHUNTER.