If you have configured the ACLs with numbering then u can remove or insert between the numbers without any issues.
If you havent done them with numbering then would suggest to copy the ACL in a notepad and arrange/modify the list accordingly as per the requirement.
before removing the old one & applying the modified list do a confirmation check whether its been applied on any of the interface using access-group command.
If yes remove the same from the interface using no access-group and then remove the access list from the global config.
Even a single no access-list 101 will remove the whole ACL numbered 101.
Then you can apply the modified one on the global config and reapply the same under t he interface config.
inline with ur second query i dont think its possible to check out the critical temp using show command but u can make use of the snmp traps send for temp which can be captured in the external server and can be monitored.
do refer this link for how to configure the snmp traps for temperature..
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...