There are 3 graveyards in Inverness City Centre (Chapel Yard and Greyfriars which are both adjacent to Friars Lane, and Old High Churchyard which is only a hop step and jump away) but they were about full by then. Chances are he is interred in Tomnahurich Cemetery, and an enquiry to Highland Council Cemeteries Dept at Kilvean Crematorium/Cemetery (which is way out of town, off the Fort William road) should tell you whether he is in Tomnahurich or not, since you have a date of death. The office telephone number is 01463 717849