I bought a new dash for mine and it cost $1000.
Some numpty before I bought my GTR thought a Monster Tacho screwed to the dash with a shift light was a good idea.
Yours is in good cond for age.
I have tried and been successful on a door to remove air bubbles by creating a few small pin holes to let the air out, insert a small amount of contact glue using a syringe with ,2 needle, heating the area with a hairdryer and applying pressure till secure. Even just using a hairdryer to heat existing and stick down may work.