Slacken off the block mounting bolts (on the rear), apply the brake and re-tighten. This may sort it out.
If not, have a look at
this post, it will help with toe-ing in, credit to
@Spinney.
I have the same pads and mine have never squealed, toe-ing in doesn't seem too critical. However it would appear yours' is at the opposite angle which wont help. I like those pads and have bought more. They brake better on my Alexrims than the Mavics
But are excellent in the dry on both. Put a few miles on them before using in the wet if possible.
They were a massive improvement on my OE blocks.
Incidentally I have one I can't get at the correct angle but it's due to a twist in the caliper arm (poor quality of my unbranded caliper), not the Clarks pads.