Welcome Steve, thanks for the introduction! It's great to see people getting back into the hobby after a long break.
So much has changed in amateur astronomy and casual stargazing in the past 10 years, even the past 5 years! Big scopes are so much more affordable and within reach of almost everyone.
A 15" Mark Suchting mirror will be beautiful in a home-built scope! Good luck with it.
And although I said it before,
to IIS! Enjoy your stay and I look forward to seeing the progress of your scope as its built!