Turn Jquery function into pluggin - jquery-plugins

Question

I recently received some excellent advice for writing some jquery functionality. I am trying to turn it into a pluggin.
this is the code that I got from stackOverflow#micha at this link
https://stackoverflow.com/a/8820946/729820
$('#DischargeDateTimeMask').keypress(function (e) {
var regex = ["[0-1]",
"[0-2]",
":",
"[0-5]",
"[0-9]",
"(\\s)",
"(A|P)",
"M"],
string = $(this).val() + keyboard(e),
b = true;
for (var i = 0; i < string.length; i++) {
if (!new RegExp("^" + regex[i] + "$").test(string[i])) {
b = false;
}
}
return b;
});
function keyboard(a) { var b = a.charCode ? a.charCode : a.keyCode ? a.keyCode : 0; if (b == 8 || b == 9 || b == 13 || b == 35 || b == 36 || b == 37 || b == 39 || b == 46) { if ($.browser.mozilla) { if (a.charCode == 0 && a.keyCode == b) { return true } } } return String.fromCharCode(b) }
I personally attempt to turn it into a pluggin like so...
(function ($) {
$.fn.simpleTimeMask = function () {
$(this).keypress(function (e) {
debugger;
var regex = ["[0-2]",
"[0-4]",
":",
"[0-6]",
"[0-9]",
"(A|P)",
"M"],
string = $(this).val() + keyboard(e),
b = true;
for (var i = 0; i < string.length; i++) {
if (!new RegExp("^" + regex[i] + "$").test(string[i])) {
b = false;
}
}
return b;
});
}
(function ($) {
var methods = {
keyboard: function (a) {
//THIS
var b = a.charCode ? a.charCode : a.keyCode ? a.keyCode : 0; if (b == 8 || b == 9 || b == 13 || b == 35 || b == 36 || b == 37 || b == 39 || b == 46) { if ($.browser.mozilla) { if (a.charCode == 0 && a.keyCode == b) { return true } } } return String.fromCharCode(b)
}
}
});
function keyboard(a) { var b = a.charCode ? a.charCode : a.keyCode ? a.keyCode : 0; if (b == 8 || b == 9 || b == 13 || b == 35 || b == 36 || b == 37 || b == 39 || b == 46) { if ($.browser.mozilla) { if (a.charCode == 0 && a.keyCode == b) { return true } } } return String.fromCharCode(b) }
})(jQuery);
Notice how I have two functions that attempt to do the same thing. One I think would be a function that would be called by a user of this pluggin, the other would be used internally. Anyway, I got this thing all compiled and I attempted to add it to my project, but as expected, it did not work. What would be your recommendations for building this pluggin?