I can't offer any advice, because we are going thru the same thing next Monday with Brady who is 9 months old. I had him at the vets today and I really don't know what it involves with the neutering. I mean, I know what they do...lol, but not what the prep work involves, nor the healing. I don't even know what tests I should tell them to do.
We have went back and forth here at our house not knowing if we should neuter him or not, after hearing about those that didn't come out of the surgery. Yes, it is scary, and we are scared and unsure here.
They also told me today that I would pick him up between 4-6 that evening.
Hugs to you and your puppies!