Editing dhcp request for one port (vendorclass, dnsmasq)

[iFloris]

Hello,

I've been trying to figure out how to edit the dhcp request for a single port.
The reason for wanting to do this is that I want to reroute iptv over my entire network.
There is a (dutch) guide for doing this in dd-wrt here.

The process appears to consist of three steps.
1. spoof mac address (which is easy in pfSense)
2. edit dhcp request, specifically a vendorclass and additional dns-masq options

Enter Aminoaminet130fisys (or Aminoaminet110fisys) in the 'Set Vendorclass' option
At the Additional DNS Masq options enter: "dhcp-option=43,08:10:68:74:74:70:3a:2f:2f:77:2e:7a:74:36:2e:6e:6c:2f:10:10:45:75:72:6f:70:65:2f:41:6d:73:74:65:72:64:61:6d"

3. allow multicast streams (also easy in pfSense).

So I'm stuck at step two, but it's probably just something that I've overlooked.
Could someone please point me in the right direction?