Ed, 
Another alternative is to use shellac to tone the sap wood and in 10 or 20 years
when the color has changed on the heartwood, the shellac is easy to take off.  I
did this on a bedside table to blend in the sap wood. I used an amber shellac,
then a garnet shellac with a little alcohol dye in it to match the rest of the
wood. Worked for me.

$.02

Brent

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