Potty Practice

We've been working on potty training Evan a little bit at a time over the last month or two. So far there are four main challenges we're facing:

1. He is pretty unwilling to go pee in the potty unless we're changing his diaper anyway, at which point if he wasn't wearing a diaper it would already be far too late;
2. He insists on standing up to pee, so the degree of difficulty is a little higher;
3. He likes the idea of pull-ups and big boy underpants but resists even trying on either; and
4. He vehemently refuses to even think about going poop in the potty.

The first three issues are all things we feel like we can make progress on, but on the fourth he's been quite recalcitrant. We now consider it a victory just to get him to sit on the potty even to read a story (which should be good practice for pooping, right?):