You would want to be careful in those applications to ensure that they were engineer designed/certified for the required SWL and that you had a qualification that you could demonstrate in the unfortunate event of failure. Most legislation will at a minimum state "a competent person" when referring to repairs and modifications to lifting gear. Repairs and modifications are also the first thing that an inspector will look for when an incident occurs.
Not saying you aren't competent, just that in todays climate you need to demonstrate innocence.