I noticed recently that my low speed fan hasn't been turning on so for now I have it rigged for high speed when ever the car is running but I don't want to leave it this way. Im not overly good with relays and such but my friend who is an electrical engineer said he would be happy to replace the relay for me. I know these boxes are sealed(rivets) but can we drill them out and replace them with bolts? will drilling out the rivets destroy the entire thing? Are these relays even replaceable once the box is open? Thanks for any advice.