I'll never forget the first time I inserted the life extending unit into a robot woman's back port. It was much too big, and I had to really cram it in there, even using a shoe horn at one point, and some WD40. But in the end it was worth it.
Three months later she found someone with a smaller unit, but a good paying job - so I guess things worked-out for her. Still, you never forget that first time using the old life extending unit - no matter how many times you've inserted it since.