[MENTION=444246]imgain[/MENTION], there's a bolt you can access at the bottom of the stem which will loosen the clamp and allow you to adjust the angle or replace the bars. You mention the main issue is the height and angle of the bars. As you probably are already aware, you can also raise the stem (minding the limit line marked on the stem) by loosening the bolt under the removable cap with the Modolo logo.

Btw, I used a similar Modolo stem for many years without any issues. However, I've read and seen other reports of failure (for example, or another example citing recall). These reports of cracked stems may be overblown, but it's something to at least be aware of since a sudden stem failure is obviously something to be avoided. At the very least be sure you get the correct size bars if you replace the current bars.