If perl/lib/ExtUtils/Install.pm is missing, then it has been removed ... and if that's the case then who knows what else has been jiggered with.
It's not so much the location of the file that's important, it's that your Strawberry-5.24.1 perl/site/lib/ExtUtils/Install.pm is quite different to my Strawberry-5.24.1 perl/lib/ExtUils/Install.pm.
You reported the following content for your Install.pm:

7 use File::Basename qw(dirname);
1165 while(my($from, $to) = each %$fromto) {
1187 my $dirname = dirname($to);
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For those line numbers (of 7, 1165 and 1187) my Install.pm has:

7 use Carp ();
1165 Filenames with the extension .pm are autosplit into the $autospli
+t_dir.
1187 next;
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In my Strawberry-5.24.1 Install.pm, there is no mention of any variable $dirname.

If you run dmake instead of dmake test do you get an error ?
If there's no error (or even if there is), you could try running the tests by entering:

"C:Strawberry\perl\bin\perl.exe" "-MExtUtils::Command::MM" "-MTest::Ha
+rness" "-e" "undef *Test::Harness::Switches; test_harness(0, 'blib\li
+b', 'blib\arch')" t/*.t
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And you could try installing the module by running:

"C:\Strawberry\perl\bin\perl.exe" -MExtUtils::Command::MM -e cp_nonemp
+ty -- Magick.bs blib\arch\auto\Image\Magick\Magick.bs 644
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Cheers,
Rob

Update:
For reference, that test command will, if run successfully, output:

t/blob.t .......... ok
t/composite.t ..... ok
t/filter.t ........ ok
t/getattribute.t .. ok
t/montage.t ....... ok
t/ping.t .......... ok
t/read.t .......... ok
t/setattribute.t .. ok
t/write.t ......... ok
All tests successful.
Files=9, Tests=273,  2 wallclock secs ( 0.00 usr +  0.00 sys =  0.00 C
+PU)
Result: PASS
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