I just finished the Merc Redstone about a month ago, so it's still fresh in my mind!
First of all I would say do NOT build this thing in the order of the instructions, you will be sorry. Before you do a thing, go over to EMRR and read the reviews on this, it will tell you the correct order as far as exactly how to make this a great model.
Ok, as far as the tower goes, I will just tell you what I did and one thing you need to watch out for. I put together the top part of the tower first, i.e. everything except the "legs". I then painted it all with Testor's flat red. Next, attach the legs to the finished capsule one at a time, do not attach them to each other until all three are on top of the capsule. Once all three are on, then join them together. Finally, attach the top of the tower assembly to the legs. Here is where I discovered the gotcha that you need to be aware of. On mine when I put on the nozzles, they were pointed down too much and not out enough, so when I got to this final step, it did not go on without the nozzles breaking off the top part of where the legs connect with each other. You will know what I mean when you get to it, but just make sure those nozzles are flared out a bit when you put 'em on.
One other thing I will say is make sure to test fit everything before gluing, that will save you headaches! Also, on the capsule you may have to do some sanding to make it go together, just go easy and don't sand too much!
Overall, I am happy with how mine came out, although there are a few flaws that probably only I notice. I posted some pics up here in this section if you go back a couple of months you will find it, I think the thread says Mercury Redstone. I would repost the pics but I am at work right now, perhaps I will be able to later.