As far as i am lead to believe all bugeye and upwards are aluminium bonnets, i could be wrong though. The kits i have for these are to suit aluminium so if someone has a bonnet that is steel i would just need to get more pressure put into that set. With the GC8 struts i am doing i have 2 different pressures as majority of them are steel but there are a few alloys floating around. If anyone can confirm for me that bugeye onwards has aluminium bonnet only that would be great.