I'm very familiar with Windsor Park and if you have the somewhat typical carport adjacent to the home to the far left or right, you can do a nice conversion. Other opinions about losing parking are valid though - so if you can replace the covered parking spot by extending toward the curb then you'll soothe any future buyers concern about parking. And yes, pulling a permit in such a popular neighborhood is a must. Here's a link to the City of Austin Development Center - be ready to be patient!! (Sometimes it's as cost-effective, and a very definite value-builder to do a simple addition on the back of the home rather than enclose parking...
And of course, be SURE to get permits!
Best of Luck.