I haven't read this entire thread, so I'm sorry if some of it is repeated.
We have processed several cockerels. I have not made it to the killing part yet, my DH does that - though I have put down several chicks. Mostly, with a larger bird, I'm worried about not getting a clean whack, or whacking my fingers in my nervousness. But I do everything once it's dead.
The first few times are not easy, I'm not going to lie. Especially the killing part. It doesn't help much when your DH says, are you sure? He's a pretty one. The killing part gets easier in that you are better at making it quick, but it's never easy from what my DH says. He has botched one, and he said that was horrible. He couldn't get another whack, so he had to let him bleed out. He also had one crow once the head was removed and that creeped him out. We will probably get a killing cone soon and try that way. Right now it's been a stump and a hatchet.
The gutting, plucking, etc does get quite a bit easier in time. The things that creeped me out the first few times I did it was the smell of the feathers when I scalded and reaching my hand into the body cavity and having it be warm in there.
Hand plucking is easy. Put a few drops of dish soap in the water and get it to boiling. Dunk and swirl around a bit and pull it out. If you leave it in there too long, you will rip the skin when you pluck. Start with the tail/wing feathers as those are the hardest to get out. The rest come off really easily, but they will stick to your hands, so have some cool water there to dunk your hands and get the feathers off.
Joel Salatin has some great videos on processing as well. You can find his stuff on YouTube.
A sharp knife and poultry scissors are helpful for the gutting and taking off the feet. I've heard the feet (when peeled) make great soup stock, but I haven't done that.
If your boys are 7 months old, you will want to slow cook them or they will be tough. I like to process around 20 weeks.
The first few times I soaked them in water in the fridge. I have found I like it better if I bag them up and stick them in the freezer right away. That will also give you the ability to get over the shock of processing before you cook them.
I try to look at processing my own birds that these birds had a great life while they were with me in the sun and happy. Grocery store chickens don't even have that. Also, by killing your own animal, we find we eat less of it and we certainly don't waste any of it.