I see how markpoints would help, but I'd at least wait until the first gun run if I haven't otherwise attacked the tank, or its unit prior since this causes them to relocate.

I can definitely vouch for the method I described working. At lower angles the shots are too spread out and you're exposed to the AA HMG. From high altitudes and dive angles it just won't be able to get to you until you're egressing, at which time you'll be out of range very quickly. Just make sure that you're not still shooting at .4nm and you should have plenty of opportunity to pull out, disbarring unusual surrounding terrain features.