to delete second installation of Trisquel 11 on a different partition

Hi,

I had a Trisquel 11 installation besides Windows (which I don’t use).

The harddisk was running slow, so I changed that to a SSD harddisk.

After that I had to install Trisquel 11 again on a different partition,

because the cloning with a Win programme of the harddisk deleted the
Trisquel GRUB bootloader;
and it was necessary to get GRUB again for the start of my first
Trisquel 11 installation.

So I have now 2 Trisquel 11 MINI installations.
How can I get rid of the second Trisquel 11 installation, so that the
original Trisquell 11 is not touched and can be booted.

How can I delete the entry of the second Trisquel 11 installation in the
bootloader?
because to formate the 2 partitions with Trisquel 11 (one for /root, one
for /home) doesn’t delete the boot entry, AFAIK.

--
Kind regards

Gottfried