I think you're pretty much stuck with the method you've already mentioned, having 2 seperate text boxes! They're two methods I've used:
One way would be to create a label and size it to fit all the way across the page. Then I place a capital
X in the label, then set the bold and center attributes. Then I move the label to either just above or just below where the centered text needs to appear. I then use this as a guide in the placement of the text, switching from Design View to Preview. This isn't perfect, because the length of the "Report Unit Type" will vary.
The best way, where it will be truly centered, is to have it appear on two lines, one under the other. Use the same technique as I mentioned above; create each textbox and size it to fit all the way across the page. Then set the Center attribute on each, and the Bold attribute on the textbox you want bolded. It would look something like this:
Report Unit Type
Registration
Good Luck!
Linq ;0)>