Okay, I have indeed done the 26" mtb to 27" wheel conversion. If you have the tire clearance and the drilled out points in the fork and rear; short reach brakes should have no issue reaching them. Now we need to talk shifters and levers, going drop bar changes the game obviously so you'll need road levers (sounds like you have those), and then to decide on shifters, we'll assume you don't have DT mounts, thumb shifters on that flats of drop bars are okayish, brifters IMO are the best choice (they currently make a070's btw 2x7).

So now reviewing your list, you appear to be set actually. Your only possible issue being clearance, now bear in mind my 700x28's were smaller than my 27x1 tire so you'll want lots of room in the rear and fork or it's just not going to work.

Other issues I've noticed, steering may drastically change necessitating a much longer stem, or possibly switching to a road geometry fork, your BB will be much higher up, so make sure you frame size is rather small for yourself since you will be raising it overall. If I think of anything else I'll get back to you.

Here's a mid 80's rigid 26" mtb converted to a 27" fixed gear (brakes and such were added after this pic)