I'm very grateful to the people who have contributed to this debate, which has arisen as a result of a set of drawings Dave Baker is kindly producing for my Fiji class book.
The position is not entirely clear cut and I thought it might be interesting for some to hear the competing arguments on either side, based on the information I currently have to hand.
There are essentially three main arguments that suggest Fiji was not fitted with a catapult, at least during her early career. These are:
1) A set of photos taken at builders John Brown after Fiji commissioned for trials in April 1940 clearly show the catapult as being absent.
2) The builders plans held by the National Maritime Museum, also showing the catapult absent. These were updated in July 1940 when Fiji was subject to some small modifications post completion of work up but these updates do not show the catapult installed.
3) As Dick points out, official documents - the Pink Lists and CB 01815B - suggest the catapult was not installed and no aircraft were permanently assigned.
As I understand it - and I apologise in advance if I'm misquoting him - Alan believes that the catapult was installed after trials commenced but before their completion in mid-May. There would probably (just) have been time to do this. However, my current understanding is that the original, pre-war plan was for Fiji to have her catapult installed in a Royal Dockyard - quite a common practice pre-1939 - and I'm not sure the revised wartime arrangement of fitting the catapult at the builders yard would have been operative as soon as early 1940.
The other piece of evidence supporting the installation of the catapult is reference to handling trials of an aircraft with respect to the ship's cranes at some stage during her work up period. I don't currently have access to this full report but the (secondary) source makes no reference to actual catapult operations.
It is also, of course, possible that the catapult was installed during the course of repairs to the torpedo damage Fiji suffered in September 1940. The official lists suggest this didn't happen but they were not always up to date.
I aim to examine Fiji's logs when the archives reopen to see if they shed more light on the subject (fortunately almost the full run has been preserved). I also continue to search for photos that might shed further light on the subject. However, my current thinking is that the balance of evidence suggests neither catapult nor aircraft were ever allocated to the ship. As some have mentioned, the photos that are available tend to support this stance. Moreover, I've taken the view with Dave that it's better not to show the catapult as we do know conclusively that Fiji did embark on trials without it so any drawing without the catapult is going to be accurate for at least this stage of her career!
Finally, I'd note how impressed I've been with Dave Baker's focus on getting these drawings absolutely correct. This has even extended to a discussion on the folding benches installed along the forward superstructure of some members of the class.