Well, there a whole lot of ways to "skin this cat" as they say. None of them are officially the wrong way, but I will give you a couple of ways to do it.
1) Using an angled plane:
a) You can create a plane that is 15 degrees from your sketch plane
b) Then use it as the direction for your extrude
2) Using another sketch for the direction
a) Create a second sketch on a plane that is perpendicular to your original sketch plane and sketch a line 15 degrees off of vertical.
b) use the line as your direction vector for your extrude
Those are two simple ways to do what you want. If you want more ways, just ask. *grin*
Thanks worked great.
If you want to use your sketch 13 in your model then select the sketch, select extrude cut then make make sure the option for "Flip side to cut" is checked.
Using this though will give you a strange flat on the edge of your spacer.