When I rebuilt my 302, I wanted to make it visually bigger as it looked quite small in the engine compartment (sits low in the frame). The trick I used was Ansen 1 3/8" valve cover spacers (Speedway Motors #135-4002 for 289-351w motors) along with tall Ford Racing valve covers. It looks better now. Check out the before and after below.

Milner

1.Before.jpg2.After.jpg