Sunflower seed quandary

Shelling sunflower seeds.This has to be the epitome of slow living - in fact too slow for me unless I can come up with a better process.

We had a lovely little crop of sunflowers over summer, and i dutifully saved the heads, hanging them upside down in the carport in big paper bags.
This week I decided it was time to attempt to harvest the seeds to use in the muesli. It has not been an altogether pleasant experience. Firstly just getting the bag down - I was anxious that a rat or mouse may have found it an ideal home...but fortunately they were uninhabited. At least, not by rodents.
Little caterpillary bugs had invaded the fibre of the heads, but not the seeds. Rather like weevils. Next issue was extracting the seeds, as I have a strange dislike of the texture of things with holes - like what is left after the seeds come out.

I had read on the net that the seeds could be soaked in brine and then roasted. The soaking removed a lot of the debris - and i thought would kill anything lurking in there.
That done I roasted them in the oven for a short while. They came out yummy, but getting a tablespoon of kernels took about half an hour. My process was rolling them with a little rolling pin to crack the outer husk, without hopefully smashing the whole kernel.
There has got to be a better way ...anyone?

It's a lovely mild day here today. Derek took this photo on his way to work. I love this shed view - it makes me happy whenever I pass it - something about how rustic it is with the verdant hills behind it - especially when the light catches it against dark skies.