I looked at the info sheet for the engine but it shows them all in the middle and only one side

the wheels can off the frame, but I have put them back on, the only problem is the drive bars from wheel to wheel are not lined up right and I do not know how they should be so that it will work.

My son's 4-8-4 fell off the table and the 8 drive wheels came apart, how do you get them lined up right so that it works and runs without locking up the wheels.