how to downgrade npm 6.14.8 to be compatible w/ node 8.10

[thesoulpole]

Hi, I upgraded (foolishly) npm from 5.6.0 (which I had from installing node 8.10, which I need for a software package) to 6.14.8.
Now it will not run, to downgrade. I get this: (even with version switch I get the same):

pi@raspberrypi:~/kettlerUSB2BLE $ npm install [email protected]
npm does not support Node.js v8.10.0
You should probably upgrade to a newer version of node as we
can't make any promises that npm will work with this version.
You can find the latest version at https://nodejs.org/
/opt/nodejs/lib/node_modules/npm/lib/npm.js:32
#unloaded = false
^

SyntaxError: Invalid or unexpected token
at createScript (vm.js:80:10)
at Object.runInThisContext (vm.js:139:10)
at Module._compile (module.js:616:28)
at Object.Module._extensions..js (module.js:663:10)
at Module.load (module.js:565:32)
at tryModuleLoad (module.js:505:12)
at Function.Module._load (module.js:497:3)
at Module.require (module.js:596:17)
at require (internal/module.js:11:18)
at module.exports (/opt/nodejs/lib/node_modules/npm/lib/cli.js:22:15)

[si458]

you need to uninstall the current version first, then reinstall the old node

# This line will clear existing nodejs
sudo rm -rf /opt/nodejs;
# Remove existing symlinks
sudo unlink /usr/bin/node;
sudo unlink /usr/sbin/node;
sudo unlink /sbin/node;
sudo unlink /usr/local/bin/node;
sudo unlink /usr/bin/npm;
sudo unlink /usr/sbin/npm;
sudo unlink /sbin/npm;
sudo unlink /usr/local/bin/npm;
sudo unlink /usr/bin/npx;
sudo unlink /usr/sbin/npx;
sudo unlink /sbin/npx;
sudo unlink /usr/local/bin/npx;

[thesoulpole]

so just installing the 8.10 version (using the command $ wget -O - https://raw.githubusercontent.com/sdesalas/node-pi-zero/master/install-node-v8.10.0.sh | bash) will not do it? I need to do the rm, unlinks first?

[si458]

so just installing the 8.10 version (using the command $ wget -O - https://raw.githubusercontent.com/sdesalas/node-pi-zero/master/install-node-v8.10.0.sh | bash) will not do it? I need to do the rm, unlinks first?

in theory the scripts already have the uninstall commands in them so you could just run the script again in theory