Jon's way is the easiest way.
To make a good, smooth, CONSISTENT cow out of these setups, you need to either use shrink tubing or medical/rubber tubing. I prefer the rubber tubing. It makes a TON of difference in how easy the call is to run, and its one more thing that keeps the guts consistently tight.
If you are using a MT2 drill bit, then that'll work to keep things tight.
I tend to use athletic tape and glue to keep all of my stuff tight.....the glue goes through the athletic tape, so it is actually just a consistent pressure for the guts until the glue dries in place. This is with using a 43/64 drill bit, because 5/8 takes to long to mess around with fitting correctly.
I suppose the two RIGHT ways to do it are to turn the guts down and use o-rings, or use a MT2 drill bit.
Here's the tutorial on turning the guts down. Its not as easy with these type of guts as it is with crow guts, but it will still work very well.
http://thogamecallsforums.com/index.php/topic,12218.msg92333.html#msg92333One more thing......putting these type of guts in and not securing them with either an o-ring or glue is just asking for an unhappy customer to have their guts fall out in the mountains.
Parker