Should just be able to bob that direct to the +_ and your done.
Make looks more hassle then it's worth and if you don't remove every part you could get a nice short.
Was thinking a quick way of checking battery's, just had a brain wave, one of these off eBay for a couple of quid, ripp out all the internals and fit a volt Meter screen in the side, will be able to test all different sizes
Should work
Now thats a great idea!