i bought a aftermarket griffin aluminum radiator and i would like to know what is that sensor for and would i have to transfer it over to my new aftermarket radiator or could i just ditch that sensor

 

that is the coolant level sensor , you can swap it to your new radiator

 

if you dont wanna swap it, just ground it out, but you'll miss out on that lovely buzzing sound when you lose your coolant.

 

I have the same issue -- I was looking for an aluminum nut or bung of some type that I could have welded in place on the top of one of the end-tanks. Problem was I couldn't find anything local, so I didn't bother. At the moment I'll just ground the connection and keep an eye on my coolant level. Back in the good 'ole days, there was no buzzer, so I've got little concern with it at the moment.

If I ever locate a cheap nut or bung, I might go back and weld it in...