Vickers Aviation trials Mosquito NF-30

Can anyone suggest how I might research an NF-30 that was not operational with the RAF at any point (it is thought) but was used by Vickers as a test/trials plane for reasons unknown? My uncle flew RK945/G on its last flight, since he crashed it, receiving fatal injuries, at Brindley Heath (Staffs) in 1948, either leaving or arriving at 51MU. Are Vickers’ records available anywhere?
Thanks – hps