What brand lifters do you have now?
This is actually important unless you (very possibly) don’t mind ordering two pushrods that have different lengths than the rest.
I have the Lunati 71977PR lifters. That actually brings up a question - I still need to measure for my new pushrod length, since I'm using a new cam and lifters. I suspect stock pushrods won't be correct. Seems I would need to do that first, right? Not meaning to turn this into a tech thread, but this is my first rebuild. Lots of learning to do.