*G* Just a tip for the puppia..
If the pup is treat motivated (Holly wasn't, Amber is) then it's simple. Hold the puppia spread ready to go over the head- make sure it's plenty big enough to go over easily. If it's a struggle, stop AT ONCE and invest in the next size up. I'm speaking from experience here.. I made the mistake of having Amber in a small puppia when it was just a little too small to go over the head, although it was much too big when actually on. As a result, she needed to be retrained to accept anything going over her head and this is how I did it.
Remember the pup shouldn't be walked for any length of time anyway, so even if the puppia is too big you can at least walk her around the house and garden to get her used to it. She'll grow into it.
As I was saying, though, hold the slightly-too-large puppia spread ready to go over the pup's nose (like you would a baby's vest) with one hand, and hold a treat in such a position that the pup has to put her nose through the hole to get at it. Worked every time with Amber and now when she sees the puppia she sits prettily and sticks her nose straight in it! Makes life a lot easier. Amber will walk reasonably on the harness, but goes crazy if I try to attach the lead to her collar- and harness walking is better for them anyway, so I haven't persisted with it.
Holly - 7years
Amber- 3 years