I found this paper on Grandpa's desk. Seemed like a tribute to me. His mediocre poetry notwithstanding, it seemed interesting with many familiar words.
To Sir(s)
Eyes on the target, finger on the gun
Let me tell you again, it was twice as much fun
Kill or die, the end came too soon
Always on top, with view of the moon
It was thunder down under, from no to never
Like gold and diamonds, you live forever
With Love
What was this about? Who was he writing to?
Grandpa's writings appear to be a tribute to:
James Bond
In particular, it contains a great deal of words which can be found:
In the titles of particular films (and stories) which feature James Bond. Specifically, where some of the keywords appear in multiple James Bond movie titles there is one (occasionally two) that is more relevant than the others to the final answer...
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To Sir(s)
Eyes [For Your Eyes Only] on the target, finger [Goldfinger] on the gun [The Man with the Golden Gun]
Let [Live and Let Die] me [The Spy Who Loved Me] tell you again [Never Say Never Again], it was twice [You Only Live Twice] as much fun
Kill [A View to a Kill (most relevant)] or die [Live and Let Die (most relevant)], the end came too soon
Always on top [Octopussy], with view [A View to a Kill] of the moon [Moonraker]
It was thunder [Thunderball] down under, from no [Dr No] to never [Never Say Never Again (most relevant)]
Like gold [Goldfinger / The Man with the Golden Gun (most relevant)] and diamonds [Diamonds Are Forever], you live [You Only Live Twice / Live and Let Die] forever [Diamonds Are Forever]
With Love [From Russia With Love]
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Note that I have ignored the smaller words which appear in titles, such as 'the' and 'to'. Also, note that Never Say Never Again was not technically part of the official James Bond franchise but is more an independent reworking of 1965's Thunderball.
Specifically, then, Grandpa is writing to:
Sir Sean Connery and Sir Roger Moore - the two knighted actors to have portrayed James Bond on film - as the movie titles selected in the piece of writing are all those which starred one or the other of them:
Sir Sean Connery - Dr No (1962), From Russia With Love (1963), Goldfinger (1964), Thunderball (1965), You Only Live Twice (1967), Diamonds Are Forever (1971), Never Say Never Again (1983);
Sir Roger Moore - Live and Let Die (1973), The Man with the Golden Gun (1974), The Spy Who Loved Me (1977), Moonraker (1979), For Your Eyes Only (1981), Octopussy (1983), A View to a Kill (1985).
This answer makes sense of:
The opening line, To Sir(s), where 'Sir' is capitalised, just like the title bestowed upon somebody who has been knighted. (See @El-Guest's answer for a nice additional connection between the Bond franchise and the song, "To Sir with Love"...) The fact that this letter is written to two people also makes sense of the phrase 'it was twice as much fun', and the phrase 'from no to never' references the first and last films of Sean Connery's time as Bond.
Finally, I hope that this is just an open letter or a piece of poetry that Grandpa has written, and not a piece of actual correspondence to which he is expecting a response...
Because Sir Roger Moore passed away in 2017!
I believe @Stiv has nailed most of the references, except
To Sir, with Love is a famous song by Lulu, a Scottish singer who also sang the title track for The Man With The Golden Gun.
Therefore this is addressed to
The actor who played James Bond in that film, Sir Roger Moore, CBE (who recently passed three years ago).
