JDL, Perhaps if you posted a photo of the shift box in question someone could tell you how to proceed. Trying to explain this with words may seem simple to people who know what that problem is but it can also be confusing to you.
Please be careful... Concrete blocks are dangerous enough under a soft tire but with a hard surface like an axle your odds of it shattering just went up 500%. If you ever saw a block mason work, you'd understand the danger.
You're like an adopted son to a lot of people on this forum and we went to bat for you when you asked us to help convince your mom to let you get the truck, so just imagine how terrible it would be if you got hurt, not just for us but your family.