From what I've heard about it over the years, a big factor in what's holding up the completion of the project (other than the usual lack of funding) is the hugely ambitious scale of the project...supposedly, you could fit all 4 heads from Rushmore onto Crazy Horse's forearm, or something along those lines...in any case, it IS a really big dig, & as was pointed out, takes some finesse in terms of controlled demo work to blast away the excess w/o taking off too much...

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