Software like Macrium lets you compress the image when you create the clone, so you probably won't need a drive that's as big as the NVME drive you're cloning. Just set Macrium to use max compression, even though it will take longer to create the clone and then to transfer it onto the new SSD. Macrium also lets you create a bootable DVD or USB so you can boot the PC after the new, blank SSD is installed which will let you transfer the clone onto the new drive. Just be sure to test the DVD or USB to make sure it actually works before you get too far. The first bootable DVD I made with Macrium wouldn't boot my XPS 8930... 
I have made a restore USB via Dell's program.  I need to replace the boot SSD and will be installing 1TB.  Will this restore all the various programs I have installed such as Quicken, Office, other other programs I have currently installed on my machine.  Is it a 'mirror image', or does it only do 'fresh install'. David
Wondering: about Restore USB XPS 8930