Best way to avoid mashing the gears is to switch to an easier gear or two. You have the 305, right? Shooting for 80-90rpm is a great start.

So you think you'd be more comfortable with the handlebars lower? You could swap the spacers yourself, really. You might want an extra set of hands to help hold things as you tighten everything back down, but it's not a difficult thing to do. Derek has swapped spacers on both of my bikes.