3) Finally, have someone quite young read it to you. Of course, they won't appreciate the argot of your industry. But they can still get better get the gist. Or you're depending on a recruiter to be really familiar with what you do. Also, be concerned about language they can't articulate. We often overrate the literacy in almost any industry.
Unlike a typical UK official letter format, the US has a couple of variations, the full block format and modified block format. The former simply means all elements of the letter, from the return address at the top down to the writer's name at the foot, are justified left. the latter, on the other hand, incorporates some elements to the right or centre, rather like the UK official letter format.