Run Stand or Engine Dyno

Not sure what to tell you other than that's what you have to do if you do in fact heed those warnings. Sure it's a pain but it's better than yanking the motor out to re-ring it or ruining your expensive new headers.

I know the feeling, I tend to heed those types of cover-your-*** warnings and do whatever I can to prevent failure before installation. You can check stuff until you're blue in the face but at some point you just have to take the leap and trust it's going to be alright and possibly have to do some extra work to ensure things are done properly.
I'm not arguing your points at all. I hadn't even considered a load needed on the engine to seat the rings. So thank you for mentioning it. It's something else I need to make sure I take into account. Some googling on the topic and I have read you can use a run stand to break in a flat tappet and ensure no leaks then install the engine in the car and break in the engine to seat the rings but I don't want to risk it.

What is needed to "properly load" the engine? Install the TC/trans?