Had to download Command Line Tools from Apple to get make to work, but not sure if that’s still the problem here?
cpan[8]> install HTML::Template
Running install for module 'HTML::Template'
Running make for W/WO/WONKO/HTML-Template-2.91.tar.gz
Has already been unwrapped into directory /Users/jaldama/.cpan/build/HTML-Template-2.91- 0bPiwL
Has already been made
Running make test
Has already been tested successfully
Running make install
Already tried without success
Ended up running as root for now which solved the apparent permission problem, but I will be ffollowing @daxim ‘s advice on keeping my own Perl separate.