Another simple solution for this is to run a bare heavy guage copper wire accross the top of the tubes connected to the ballast(s) ground. I've made three units this way and it works great!
Whether I go with the sheet metal or the bare copper wire, does this need to then be attached to the sockets? My ballasts are grounded and I was going to attach that ground wire into this copper wire for behind the tubes, but I guess my real question is... do the sockets need to be grounded as well?
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