Hook code to add custom field to Contacts tab in admin

[webjive]

I need some help in getting this to work. Doesn't seem to want to cooperate LOL

I'm trying to add a custom field to the contacts tab what when adding a new contact (or viewing one) there's an extra field called Phone ext.  I have the following code but it doesn't seem to show the custom field on the Contacts tab.

Thoughts? 

P.S. Kept getting a 403 error with this community when pasting in the code using the code feature.. UGH...

 

[Randal]

Were you ever able to get a custom hook into the Contacts editor to work? I would love to extend this with some custom fields of my own!