I bought an impeller puller but on my 2002 there was a "step" on the transom and it interfered with the tool so I was unable to use it.  After perfecting the technique learned here, it became much easier. 

The next best thing I did was install a raw water strainer.  I learned that all the spring debris on the water was likely contributing to the wear and cuts on the impeller.  After installing the strainer my interval on impeller changes went from 2 years to 3 years and they still looked almost new. 

2 minutes ago, srab said:

Admittedly, on my 2006 21 LSV Sunscape, the muffler doesn't run near as close to the raw water pump as it does on yours, but, IMHO, an impeller puller is one of the best investments I've made.  Makes the job so much easier.

I might try one again, but removing the pump wasn’t that bad. 

Admittedly, on my 2006 21 LSV Sunscape, the muffler doesn't run near as close to the raw water pump as it does on yours, but, IMHO, an impeller puller is one of the best investments I've made.  Makes the job so much easier.

Pump off. It was easier than I thought it was going to be. 
 

Update, impeller out with just a wiggle! Sigh, I see a few new additions to the “boat emergency bag” to make this easier. 

Compared to doing it with the muffler in place, yeah I was giddy with joy at how much easier it was.