Maybe have an option or a prompt that asks if this version is being installed   
on the same system Configure is running on, and then it should see if
perl is already installed, and if it is, use Config.pm for default values
whereever they exist in Config.pm.
 
That way there won't be very many prompts when installing Perl.

Directory names should still be prompted for, especially if they include
a version number (but give the existing directory name there so that it can
be duplicated or modified for the new version of perl.)
 
As it is, perl is a major PITA to upgrade.
 
--DK. perl@dontknow.org