Im thinking of using the front uprights of my mx5 donor as they are lighter than the sierra type, The tiger uses a tube at the top of the hob to give it height so i was thinking of replacing it with these.
Rescued attachment raceledapinkit.jpg

nice but you might see your weight advantage vanish as that's a lot of metal

http://freespace.virgin.net/bob.carter/automotive_projects.htm

have a read of the locost build