Adjusting the rolling tape guides is not simple. Access to the guides normally requires partial dismantling of the camcorder, requires the right tools, is fiddly to do and can easily result in damage to the VCR or the tape or both. Great care is needed. It is probably be too difficult for most people.
Talk is cheap. Backing up claims with evidence is the gold standard. In your position, I would seek the help of someone who can demonstrate they have successfully done this work many times before and is happy to demonstrate examples of success.
Here's at least a YT video of a tech, Colin, performing the task, and talking his way through it. As he says, only certain cases can be fully corrected.