I'd place it at the base of that tree with a brief explanation written on it and sealed in a clear urathane. I don't need a 500 pound chunk, just something 18 inches square or 2 foot surface area. I also would suggest that you auction off the remainder of your tomb for the benifit. If you wish to read this over the air, you have my permission. I'll be there for your coming out party.
Children are the future of humanity.
What adults do to and with them will shape the future of our society. In all the years I've known you what you are doing now is the most un-selfish act I've ever seen. There are kids that will receive a second chance because of the funds you raise, and the work that can be done with those funds. God Bless You Dan.