Re: Entrance size for Top Bar Hive
Sandra, I agree that with that peaked style lid using a top entrance that simply shifts the first bar is probably not practical. In this case I'd put the end entrance hole just under the overhang of the top cover.
You didn't ask about this, but I'd recommend you normally keep the "mite tray" in place even if you are not doing a mite count. In particular, have that screen closed off when you install your bees. There are multiple reports on Beesource of newly installed bees absconding from TBHs with open screened bottoms. I built in a screened bottom into my self-made TBH, but keep it closed off all the time. With the adequate ventilation from a Bush style top entrance, I have seen no need to have the bottom screen opened.
USDA Zone 7a - elevation 1400 ft