Personally I would forego trying to get apples this year, and maybe even next. Concentrate on starting to reduce the crowns a bit, and thinning the middles of the trees out for light and air penetration.
FOCUS ON PROPER CUTS TO PROPER LATERALS! SHAPE AND SIZE AREN'T IMPORTANT HERE!!!!!!
Heres how I would tackle it:
Clean ALL the deadwood out first. This deadwood is robbing you of vital space in those trees.
Then go through the center and grab anything that is rubbing. If two branches are rubbing take the one that will make the smallest pruning wound, but keep in mind the branch you leave should have a good attachment point and growth habit.
After that is done post some pics of each tree individually, and we'll see if there is enough life left to start reducing them, LIGHTLY. If not that might be all the trees can handle this year....? The 30% rule is more for younger trees that can handle it. these older trees should stay at 15-20% MAX, not including deadwood.
Get rid of that grass, and apply some compost, cover it with wood chips. Start at the trunk and put 1/2"-1", but not touching the bas of tree. taper that out to the ends of the branches, to 4" deep. This will add vigor, and keep down the grass, and other weeds competing for nutrients.
Go slow, have a reason for making every cut, and focus on making GOOD PRUNING CUTS!
Take more pics!!!!!
Massachusetts Certified Arborist