Rather simpler would be to run an asynchronous perl one-liner at the end of the script that waits a couple of seconds for the script to terminate and then deletes it like this:

P:\test>type junk.pl
#! perl -slw
use strict;

sleep 10; ## Simulate doing stuff

## Start an asynchronous perl one-liner
## sleep a couple of seconds and the delete the script ($0)
system 1, qq[ perl -e"sleep 2; unlink'$0'" ];

P:\test>junk

P:\test>dir junk.pl
 Volume in drive P has no label.
 Volume Serial Number is BCCA-B4CC

 Directory of P:\test

File Not Found
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