Advice for your Aunt Mark  

sorry, you said no more advice but no-one mentioned waterjet cutting which might do the job and is fairly common judging by some quick googling. 

I think Mark needs Plexiglass.  Maybe with inclusions -- a Florida rayfish, or tulips and waterlilies, maybe ?  Just a thought . . .
 
My mom put pineapple or grapes in the Jello.  Gad, how did I come out only partially damaged ?

I have a collection of old insects and arachnids trapped in clear plastic resin paperweights.  They're extremely low-maintenance pets!  It's tempting to imagine this on a larger mammalian scale e.g. a hog (kitty cat, child, etc. etc. etc.) frozen in in a block of lucite as a coffee table, but it's probably best to stay away from that sort of elephant-foot wastebasket cruelty...  It seems to keep coming up, though...
 
My mom does this thing with green Jello and cream cheese I think whipped together into a neato tasty texture it's kind of foamy
 
 

findagrave.com, who knew? 
I think Mark should take up that idea, head out late one night with a shovel and cast in a fingerbone or something, it would be like a reliquary.

Help now I'm excited to go home and make Jello
 
that gravestone is very suitably lacking in ornamentation, hooray for that.

The name line is centered on the slab, with the dates added below as an afterthought.  Tsk tsk.  I wonder where that marker lies . . .

Just read the wiki, he was cremated, oh well. 

I've always liked tombstones...mostly the vulgar overscale examples that are ever so slightly tilted toward the grave, and  I have absolutely no problem with faded plastic flowers adorning the beloved plot.  Also jello (minus any bones) can bring nothing but joy to the modern diet (in fact colored marshamallows floating on top of lime jello can easily unleash the beast in me!).  Tonight I'm serving a simple dinner menu, unfortunately sans the gormand "glob-o- love" called jello.  I like pants too.
Hi,
Aunt M.

Eek !  Hike that puppy up, love -- you're too young to have your bresticles down around your navel . . .
And have a lovely feast.  I bet you're the bee's meow in la cucine . . .

I'd  need 2 band-aids and a long string to hike those bad boy's up!  It's not easy.
Fondly,
 
Your Aunt Mark