Jobs in engineering have never been easy, and getting into them has always been somewhat difficult. If you think that gaining the manager's position is going to be easier, then you definitely have another thing coming. First of all, you are going to need to expand your knowledge. Even in engineer careers, your technical knowledge isn't going to be enough, and definitely won't make you a management candidate.
There are many other things that you are going to need to learn if you plan to progress in your engineering job at all. First of all you need to learn to manage projects. There are many that cannot handle the task of managing resources. Resources can include people, and they can include money. People are very important, and many times you will need to decide who to keep and who to fire. This is especially true with manufacturing engineer jobs, considering how dangerous they are. You need very competent people working, and you need to ensure that they can all work safely.
Managing the money is also difficult sometimes. You will need to keep an eye on where all of the money is going, which is an important part of jobs in engineering. You might think that you didn't get into this field to work with money, but any job is going to deal with money as you work your way up the ladder.
If you wish to expand on any engineering careers, you are going to need to do a few things first. There are many people with jobs in engineering that have been there for a great deal longer than you. That is to say that they know more than you; and you can ask them for help. Do not be ashamed if you need to ask for help, most of the individuals who have climbed to the top in the past have had to ask for help at one point or another!
Now you're going to need to push yourself, and push yourself quite well. How far can you slide out of your comfort zone? Your technical abilities are going to need to improve significantly if you are to make it into manager positions. There are even things that you will have to learn which are outside of your current job description. This may be confusing at first but manufacturing engineer jobs have always been confusing, so no surprises there.
To advance in engineer careers you're going to need to have the willpower and the boldness to reach beyond what you normally do. It's not going to be a simple process, but once you get that position that you've always wanted, you're going to find that it was quite worth it in the end, after all, have you seen the salary that managers make?