I cut out the vent from the gh guard about 1cm around the lip of the vent, then cut a hole in the scorp guard the shape of the vent so it overlapped on the inside and arc welded it (What a pain in the ass making a million spot welds so it didnt warp on paper thin metal) then grinded it flush and filled the inconsistences with filler, sound easy but a bit of a pain.
Felt kinda bad cutting up those ge vents they were mint (Or about as mint as you get on a gh) the car I took them off had electronic rust protection. but meh
Tubz
'81 GJ Scorpion, '87 GN Panel Van, '77 Sigma sedan