The forum has many examples of mid-1980s Univega grand touring bicycles, however few members post the serial numbers. However there are a couple of confirmed 1986 Gran Turismo with Miyata serial numbers. They have short but horizontal dropouts and the bridge does not match the OP's frameset. They also have low-rider mounts. There was also a higher Specialissima grand touring model, but presumably it would have been made by Miyata too.

The serial number on the OP's bicycle is similar but not identical to Merida's, a Taiwanese contractor who built for several major brands in the mid-1980s. The yen was sharply revalued in Spetember 1985 under poressure from the US government. This made Japanese manufacture less economical and many brands moved manufactuiring from Japan to Taiwan. Presumably, Taiwan was unable to handle a mass transfer, so it was phased in, with the smaller profit margin, entry level models being in the first wave. I would expect the 1986 Univega sport/touring models to have come from Taiwan.