unfortunately you cant rotate projected views, you'll have to import the drawing in iso view, then make the adjustments you like.
you will have to make a new "named view" with the proper isometric view. once you have made a new named view inside your assembly/part, you'll be able to import it into the drawing.
to make a named view, you will need the Standard View toolbar. on that toolbar, click on the last icon on the right, it's called "View Orientation" and it will pull up the Orientation Box. In this orientation box there is an icon of a viewfinder with a yellow star on it. First, position your model in the right orientation, then click on this icon and create the new Named View.
I have found that the best way to position the view in a new isometric view is by first using the ortho views and then tilting the model appropriately using the arrows (typically they rotate the model in 15 degree increments but this can be changed).
Thanks Babak and Antonio.
Both your suggestions work.