When installing mine a couple of months ago, I found that there was still a gap between the carb and the white 'gasket' and no matter how much I tried adjusting the nut and bolt balance, I couldn't get it to completely close, so once it was all in place I sealed it with a silicone sealant. This is disappointing but it's a workable solution that I suspect will need reapplying once every couple of years.....and that's as good an excuse as any to get the tuning right too.
With the air filter oil, I haven't been able to get any locally so I'll order online - does it go on the inside or outside i.e. on the filter foam facing the bonnet or on the filter foam facing the carbs?
Bobby