Coolant Leak after changing Thermostat?

[Dusty_GMT800]

I wouldn't use sandpaper unless you can see or feel something on there that absolutely will not come off any other way, but that's just my opinion

Gotcha, what would you recommend? Would something like a scuff pad work?

 

[Doubeleive]

ya its just aluminum I wouldn't use anything to rough

 

[sumo]

Gotcha, what would you recommend? Would something like a scuff pad work?

That’s perfect or a very fine sandpaper