Looking good Trevor!
My 86's Speedo seemed to stop at 120 MPH even though it felt that I was picking speed. It failed twice, just before I bought the car and a couple months later. My Dad's 505GR back in the day had the same problem, no wonder, however the rest of the gauges worked remarkably well. The GR had no tacho so I guess all we had to contend with was the gas gauge (petrol gauge) and the water temp.