Uno - prevent multiple COMM port enumeration?

Hello,
I have 20 Arduino Uno devices to program with the same program - for 20 identical instances of my project.

Each time you connect a different Uno, it enumerates a new COMM port.

Is there any way to change this behavior? I have 20 Arduino's to program and it is tedious to keep going into the device manager and deleting the COMM port of the Arduino I just programmed...

Thanks,

Steven

Use the ICSP to program them. (bootloader will be removed)

Are these stand alone or separate UNOs?

These are stand-alone Unos with a custom shield.

I don't want to eliminate the bootloader - I want to continue to use the bootloader to update code in the future. It's just that programming 20 in a row results in 20 enumerated COMM ports (unless I delete them...)

Thanks,

Steven

If these are DIP packages move the I.C.s from each destination UNO to an UNO plugged into the USB (Cable removed obviously while going so).