Does anyone know a good way to cape an elk for
a "shoulder" mount? I've done it with varying
success and just wondered if someone knows an
easy way if there is one.

It would take a long time to describe it here. However if you go to the website for the Colorado Division of Wildlife, they sell a video called "From the field to the table" that shows how to take care of a big bull elk after it's down. It covers field dressing, quartering, packing, butchering and caping.

It would be worth checking out. I picked one up for a buddy of mine from Indiana when he was coming out elk hunting and he said it really helped him.

Mac

In a nut shell
The cape should have as much shoulder hide as possible, let the taxidermist throw the excess away, therefore start at about the rear of the front shoulder.
Next make a "Y" incission one leg to each antler base the the long leg straight back the shoulder incision. Make sure the knife cut from flesh up so no hair is cut.
cut up around antler base, next work your way to ears cut thru cartliage near skull
What I do is cut through open mouth for the lips, unless you experienced start where the inside lips contact gums, careful not to penetrate hide next do the same through the eyes cut through nose cartlidge .
The taxidermist can trim as necessary he can not put it back if it ain't there
My recomendation spread a lot of salt all over hide especially inside face where the ears eyes and lip and roll it up and freeze it till it till it gets to Taxidermist, take alot of pictures of dface which can be given to taxidermist
do the typical antler skull cut more skull is better than less
good luck

If you have to pack the elk out you can actually skin it from the back down, it will give you as much cape as you will want to carry that way. ant it is easier to bone out the loins first and then cut the quarters off ...P