How do I get the back two bolt out from on top transmission on bell housin of my 2000 chrey blazer?

sometimes you have to get on top of the engine to get at them an you will need a box end wrench. unless you have the trans hanging and have a lond extension and swifels for your ratchet and socket. They can be a mf sometimes to get at

remove the transmission mount....temporarily~

Drop the engine and trans a little bit. Once yoy get them out, bolt back the trans and pull the engine, or if it is the trans you are removing, re-attach the engine and pull the trans.

take a ball peen hammer and keep punchin' the firewall with the peen end.....ok, not really, but is THE caveman solution~

Make sure if it is a Chevy engine to remove the distributor, and carburetor for easier access. A super long socket extension with a knuckle extender is sometimes helpful to reach it after dropping the engine and tyranny a bit.