Killed black widow with bug spray, how to preserve body

Was unraveling the hose when I saw this spider attached to the hose. Was visibly black, but upon closer inspection it had a red hourglass, so I killed it with bug poison (took awhile). Now, I would like to preserve it's body as a souvenir. Suggestions?

The alcohol should be OK for a while, but over time, the abdomen will shrivel.
It will have to be soft to encapsulate it, if it dries, it will become brittle and positioning it will break.

Personally, I keep them live as pets, don't have many where I live now.
When done professionally, critters are 'put to sleep' and encapsulated.(they just never wake up)

In the olden days when people kept heads as war trophies, they preserved them in jars of honey. You might want to try to preserve the spider in honey. Or perspex. I have a scorpion in a block or perspex. But I bought him that way.

All it needs to do is DRY...nothing else.