Comcast dhcp6c config to pull a /60 prefix delegation

dhcp6c.conf

interface sk1 {
    send ia-pd 0;
    send ia-pd 1;
    send ia-na 1;
};

id-assoc pd 0 {
    prefix ::/64 infinity;

    prefix-interface sk0 {
        sla-id 0;
        sla-len 0;
    };
};

id-assoc pd 1 {
    prefix ::/60 infinity;

    prefix-interface vlan2 {
        sla-id 1;
        sla-len 4;
    };

    prefix-interface vlan3 {
        sla-id 2;
        sla-len 4;
    };
};

id-assoc na 1 {
};