There is the Seaforth Highlanders Regimental Museum.. they gave me information about a relative who was captured at At Valerie.
Also on the net is The Burma Star Association who have the Seaforth Highlanders 1st Battalion which includes a diary of Peter Torrance who fought in Burma... the diary of events starts 25 Feb 1942.
It does not answer your orinal question but may shed some light on what your late fil endured.