Dcloser6

It just started and I had to turn on the heat full blast to prevent it from red lining. Water level seemed ok, but not sure if it was cycling thru or not.
I know it could be the thermostat and wonder how hard that is to replace.
Also are there any other things it could be?
Appreciate any help.

stock s10

T stat isn't that hard to replace easy way to check is to let it run and get up to operating temp. then check your upper and lower hoses for a temp. difference. If it is your T-stat than all you need to do is let it cool down then pop the t-stat housing(What your upper hose connects onto the intake to) off and replace, refill coolant and burp system. Only other things I can think it might be is maybe clogged radiator or water pump that took a S**t