The angle between the legs is about 85° which is the largest angle our Workmate jaws would accommodate.
Four 3" deck screws hold each crosspiece together - two from one side and two from the other. A tight clearance hole was drilled through the 'top' piece to preclude splitting which would adversely affect rigidity. Also, waterproof glue was used to ensure absolute rigidity (but mostly because this tinkerer likes to use glue !).