Fall planting is no problem if the nursery took proper care of them. The problem with plants from big box stores is that many different unskilled people are taking care of them and it is a miracle if they survive. Assuming they are healthy, they should be OK. The main problem is frost heaving in the winter if you get freeze/thaw cycles. It is best to prevent this by using a good 2 to 3 inches of mulch. This is good for the azaleas anyway.

Usually plants from big box stores are in a media that dries out quickly so they don't drown them. You can tell when they dry out by the weight of the pot. If it gets light quickly, then water frequently. If it does in fact dry out very quickly, when you plant them, it is a good idea to soak them for about an hour and get rid of some of the potting material .

They need about 3 hours of sun a day to form blossoms. With less light, they may just be nice green bushes. If it is too shady, you can either prune off some of the lower spruce branches, or move the azaleas to a sunnier location. Since the azaleas formed their buds for next year's flowers this summer, you will have to wait 2 years to see if they will bloom where you plant them now.

The best ways to acidify soil are sulfur dust or ferric sulfate. It is best to test the soil so you know how much you need. Unless the leaves turn yellow with green veins, the acidity of the soil is not a big problem. If you are in the mountains, chances are you have acidic soil. If you are in the plains, then the soil could be alkaline, in which case you would need to build up a raised bed to have a place where you could place acidic soil. It is very hard to keep soil acidic in a hole in alkaline soil. That is why they use raised beds.

Here is a link that might be useful: How to grow rhododendrons and azaleas.

Thank you for the info. I feel better. I may have to prune the spruces back, but that's okay. They are HUGE!!!