Very good, congratulations.
After getting a watch running, in all positions for a time near to the expected power reserve, the next step is to use a timegrapher or equivalent application to see how it runs.
And if you want to look it better try an ammonia based solution. You won't need any cleaning machine or ultrasonic.
I was originally struggling, trying to get the train sat on the back plate but Jersey Mo linked a few pics of his rebuild and it clicked for me. By building it up on the front plate, dial side down in the clamp, you can line the train up first, then the escape and the pallet fork rests on the balance which is just sat in place, it also helps if you loosen the balance screw a bit, it adds stability to the pallet while trying to get the smaller back plate to line up with the pivots.
I then just eyeball the back plate with the keyless works and mainspring barrel and just nudge it around with an old oiler or very gently with the tip of my finger until it sits in place.
Then loosen off the clamp, slide the tweezers in (get a reasonable grip on the whole movement) and flip it over to screw the plates in.
Takes a little while to get the knack but after a bit of practice you get used to it.