This is just a simple !access script.
on admin:text:*:#:{
if ($1 == !access) {
msg chanserv access $chan $2 $3 $4
msg $chan $replace($2,add,Added) $3 on the access list (Level: $4 $+ ) }
}
You could make your first on:text event into one, instead of having the if ($1 = !access) part.
on 10:TEXT:!access:#:{
You can also probably use "cs" instead of "msg chanserv", as most IRCds have the shortcut enabled.
There is no point for your $replace, as you don't need to replace anything. You could just leave it as
msg $chan Added .. etc