Correct shift knob available on eBay
 

Not mine, but I spent about 3 hours restoring mine yesterday only to find out that someone is selling what looks like proper ones on ebay:

http://www.ebay.com/itm/71-72-Chevy-...c75c14&vxp=mtr

The ones you would get from LMC are the mid-70s Monte Carlo thing (like the Help! packages in the auto parts store).

From the threads I found about the knob here before restoring mine people said there's no way to get it off without destroying it. Here's how I did it:

Leather glove
Rubber glove over leather glove (for traction)
Heat gun

Mount other end in vice. Try to keep it to the non-chrome area otherwise you'll see your vice marks later.

Heat up shift knob as much as you can WITHOUT ruining it. It's plastic, so don't get carried away.

Grab and pull. First time I saw a little gap open up so I just kept at it and it came off fairly easy.

Don't both trying to rotate as you pull, the shaft is splined.

Re: Correct shift knob available on eBay
 

I got the correct knob a couple years ago from Classic Industries. You just need to order the one specified for 1971-1972. Their part #CX1797. It appears to be the same as the eBay knob in their picture. I think these are marginally different from the originals, but very, very close. The texture at the end seems to wrap around the end a bit more.

Re: Correct shift knob available on eBay
 

Mine is definitely a 70 truck, though I suppose it could have been replaced at some point. More likely the catalogs have the years wrong.

Re: Correct shift knob available on eBay
 

All original trucks I've seen had this style knob. I can't say for sure that the splines and means of retention are the same from year to year or for tilt vs. non-tilt. After I posted above, I realized that I'd used this knob on one of my 71/72 tilt columns, but outwardly it looks just like the original on my 69 column as well as the other years. The van and RV tilts that I've seen also used this knob.

Re: Correct shift knob available on eBay
 

I haven't tried it, but i hear boiling water will work to pull the knob off.