OK guys, it's ok I figured it out through viewing several other script examples. So this is my final script. 
#!/usr/bin/perl -w
use strict;
use warnings;
use LWP::UserAgent;
my $netloc = "xxx.xx.xx.xx";
my $realm = "Realm";
my $user = "usercode";
my $pass = "passcode";
my $ua = LWP::UserAgent->new();
$ENV{PERL_LWP_SSL_VERIFY_HOSTNAME}=0;
$ua->default_header( "Authorization" => "Basic bGJLN0dLaGNmVTM2MkxNbjp
+zOUtKRXR0UVBHeGIyTkxkcEpMM3hHbmlLN0MwaUk=");
$ua->default_header( "Accept" => "*/*"  );
$ua->default_header( "Content-Type" => "application/x-www-form-urlenco
+ded");
$ua->credentials( $netloc, $realm, $user, $pass);
$ua->ssl_opts( verify_hostname => 0, SSL_verify_mode => 0x00);
my $url = "https://".$netloc."/api/v2/access/token";
my $resp = $ua->post($url, Content => ['grant_type' =>  "client_creden
+tials"]);
if ($resp->is_success) {
    my $output = $resp->decoded_content;
    print $output."\n";
}
else {
    print $resp->as_string();
}

[download]
And I now get the following output. 
{"access_token":"ea1dda77710f64b0db328415427a1463e74ea204","expires_in
+":3600,"token_type":"bearer"}

[download]
Thank you for taking time and steering me in the right direction. That postman console really helped me a lot. Thank you very much.

In reply to Re^3: Getting an Access Token by PerlMonger79
in thread Solved: Getting an Access Token by PerlMonger79

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