Installing a timer control part on Whirlpool washer

[Tnkrposit]

The knob on my Whirlpool Ultimate Care II washer kept pulling off when I would try to turn the dial to start the washer.  This morning I thought I'd fix that little problem by taking a pair of needlenose pliers and try to spread the two plastic prongs that hold the knob apart.  Well...of course one of the plastic prongs broke.  Now I have to install a whole new timer controller.  I have located the proper part to replace, but I was hoping for some guidance on the complexity on installing it.  Is it something I can tackle myself or should I call the repairman?  
Thanks...

Model Number: LSW9750PW3

[Repair-man]

On back of the timer is a black plastic pin that pulls out to remove the knob. If you  hold the  knob down and press the pin down into the timer body at the same time, it should lock the knob in  place. As you found out, the front shaft is delicate and should not be touched.

[Tnkrposit]

To clear up some confusion on my part....Your directions and picture are very helpful, thank you for those, but are you saying that I can just replace the post that the knob attaches to and I don't have to replace the whole timer assembly? If it is just the post portion, do you know what is it called so I can look it up to order it?

Thank you again for the help!

[Repair-man]

The mounting stem on the timer is not replaceable. The timer is a complete assembly, sorry.