Agree with all of the above, adding that whichever way you do the job, two sets of hands always makes it a whole lot easier.
I used strips of lino - that floor covering stuff - and zip ties bought in bulk from ScrewFix instead of towels. Lino's cheap, easy to cut to size, doesn't snag and is tough enough not to tear if it gets clipped by the engine casing. Cardboard works pretty well, too.
If you've got a bare frame, drop it over the engine. But again, two sets of hands.