Can't Find Seat Covers that Fit

Like the title says, I can't seem to find any seat covers that fit my leather seats. I've bought probably 4 to 5 sets of seat covers to put on my front leather seats and not one of them have fit. Now, I've returned them all but its costing me shipping and is starting to add up.

The part that does not fit is that each seat cover needs to go through the space between the top and bottom of the seat to attach to the back. Well, when reaching between the bottom and top part of the front seats it is blocked by the material on the back which does not let you connect the straps from the front to the back to tighten the cover.

Does anyone else have this problem and what did you so to overcome this so you can put a seat cover on? I really want to protect them from all the moisture I bring in from hunting the everglades.

Thanks!