Pinching too hard will result in unnatural thorax shape, so be careful with that.
Killing time in ethyl acetate seems to be around 2 h depending on concentration and moth size. With green moths one is better off with something else, though. The color tends to fade more or less towards yellow.
I haven’t had that much problems with jar damage with sufficient concentration, so I just put them in. That naturally depends on jar and moth size.