Best way I know how to balance the outfit is to put the correct reel on it (weight-wise) and lay it on your outstretched finger ... with your finger under the front end of the handle.
If it balances ... you're good to go. If it tends to dip towards the handle, it will work but may "feel" a little heavy in hand. If it tends to dip towards the rod tip, it ain't gonna work (IMHO) and will wear your wrist & forearm out with any extended use. If it "drops" towards either end of the rod ... it's too light or too heavy and you need to find a different reel.
I have heard of people putting coins or slugs inside a butt cap and placing it on the butt of the rod handle ... as a cheap alternative to those balance systems. But, in either case, they only work to counteract a tip heavy outfit. A larger/ heavier reel does the same thing and doesn't require other "pieces" to be added.