Hi TT
I cut a hole in the tank at one end the same size as the inside of the thick rubber gasket, pushed in and turned the unit until it was in the position where the float worked the best ( fuel height is more consistent in the centre when cornering ) market the position of the 4 cut outs in the outer flange and drilled 5mm tap m6.
4 bolts screwed upwards from the inside and locked with nuts, unit fitted with the std thick gasket, repair washers and nylock nuts. passed sva like this and have not had any problems. Same type of fixing as Robin Hood have used in the past.
