There was an article on the Lightning training for the Confrontation in Aeroplane (Jan 2018) which I dug out.
The Indonesian AF (TNI-AU) had 16 Mustangs, of which the RAF thought around 8 were serviceable stationed with Wing Operational 002 Taktis at Marlang, East Java.
The trial was carried out in 1963 by the Air Fighting Development Squadron (AFDS), part of the Central Fighter Establishment (CFE). The Spitfire was flown by the OC AFDS, Wing Commander John Nicholls who had flown the Spitfire XIV and XVIII on his first tour in 1946 and in combat in Malaya, had been a Meteor instructor and then went on an exchange posting to the USAF on the F-86 during the Korean War, shooting down a MiG-15. Later he was the Fighter Command liaison officer on the EE Lightning programme.
The Spitfire used was PR.XIX PS853 which had somehow survived to continue to fly with the CFE despite officially being a gate guardian and struck off charge on 1 May 1958 but brought back on the books in November 1962.
The Lightning's used were F.3s XP695 and XP696. They were delivered in January 1964 so it seems the trials were held sometime Jan-April 1964 before the Spit went to the BBMF - which is later than most published accounts which often refer to 1962 or 1963. The F.3 had no ADEN cannon capability and were equipped with Firestreak.
There was no official report on the trials, indeed the whole affair was largely unofficial with flying carried out at the end of other AFDS sorties.
Nicholls' description of the results state they discovered piston-engined fighters gave poor IR lock-on, especially in the rear aspect. A follow-up gun pass would be difficult due to the high overtaking speed making accuracy difficult. Slowing down too much put the piston fighter at an advantage (the same was found in Lightning Vs Hunter trials). It was found with sufficient warning the Spitfire could spin around to meet his attacker head-on to make the attack even more difficult.
Firestreak had limitations too, a minimum firing speed of 300kt, maximum 3g limit, the missiles would also de-arm when flaps were selected down, so could not be used in a slow turning attack with flaps deployed.
The best method was found to make a climbing attack from behind and below, where the Spitfire pilot's visibility was weakest and the IR signature most favourable. If the missile missed the Lightning pilot would continue to climb and then dive safely out of range and repeat another climbing attack.
Oddly by 1964 the RAF plans only included the Javelin's of 44 Sqn with no Lightnings scheduled for a reinforcement role. Indeed no Lightning reached the Far East until 1967. So this really was an informal test to see what could be done and how Firestreak might cope with against piston-engined fighters.
