This has nothing to do with implicit conversions. This is assigning a value to a type larger that it allows. If this were a column, you should have to implicitly change the column definition, that's just a recipe for disaster.
How to post data/code on a forum to get the best help: Option 1 / Option 2
Are you seriously taking the advice and code from someone from the internet without testing it? Do you at least understand it? Or can it easily kill your server?