Custom Extension / Custom Technology Missing

I'm currently running FreePBX 13.0.1RC1.30 and in a much older version of FreePBX I could create a 'Custom Extension' and use the 'Extension Uses Custom Technology' box to put in an outbound SIP trunk (SIP/8199@siptrunk). Basically when that extension was dialed it would just automatically forward to the sip trunk.

However I can't seem to find that same functionality now. Is that gone or am I missing something?

Thanks for the help,

-mjg