Originally Posted by TigeRyan
What I figured out was that your solder on the ends of the cells needs to be nice and shiney, so if you it dirty or a bit corroded, use a hot iron to liquify the solder and clean it up...Every pack I have done that to so far has gone in much easier....
I wouldn't apply heat to the ends of the cells any more than necessary.
Just clean the ends up with motor spray and a rag.