A Scouser went on Dragons' Den with just a rucksack and a shotgun.
Peter Jones said, "I'm confused, what's the business plan?"
"It's quite simple Peter," said the Scouser, "Just put the cash in the bag and no-body gets hurt."
Cutting a hole in a scull would negate the purpose of a scull wouldn't it?
Definition of scull
1a: an oar used at the stern of a boat to propel it forward
1b: either of a pair of oars usually less than 10 feet (3 meters) in length and operated by one person
They can 3-D print metal now
https://markforged.com/metal-x/?mfa=sga-em-tof-metalaudience&adg=81534068527&kw=metal%203d%20printing&device=c&gclid=EAIaIQobChMIkIjUqOLN5AIVFeDtCh15qgOLEAAYASAAEgK8P_D_BwE