JW51: I will caveat my earlier statement with the fact that I only needed to increase the gauge of a circuit because I was doing something strange with it. If you are wiring it up essentially stock, then you won't need to fiddle the block.
I take it you mean removing the pin and re-pinning with larger gauge wire? I also do this in certain cases - usually when using the universal kits; as sometimes it just makes more sense (and you end up with a cleaner install). In fact I did it over the weekend on a circuit for our fire truck.
I have a selection of the correct replacement connectors that lock in the box or plug. Use the right tools and take your time, it works fine. x3 on making sure all the wiring is upgraded.