I hope this question is about the engine coolant thermostat. If it is and you have to ask this, you shouldn't be allowed near a vehicle with a tool.
Remove the fuel tank for access
Replace and bleed line
No, You will have to remove the fuel tank.
Your 1999 Chevy blazer doesn't have a timing belt.
Will a 1997 blazer what work on a 1999 blazer????? If your talking engine, transmission, or running gear than yes. It is all the same.
Service brakes - replace Master cylinder Parking brake- either lubricate or replace cables ; I had a similar problem with my 1999 Chevy blazer, i ended up replacing the caliper and have had no problems since.
Check related answers. There are several responses and are quite accurate.
How to change the bulbs in the climate control for a 1999 Chevy trailblazer
Mostly, yes.
how to drai torque converter on 1999 chevy blazer
These are low voltage sensitive. .Replace your car battery.
NO. Not even close. Chevy redesigned ALL the TRANSMISSIONS and ENGINES in late 1999. Anything above 1999 WILL NOT FIT anything under 1999.