Looking at what a lot of Mini builders are doing lately and having their mast step way forward I thought I would try it too
Here is my effort Tried it out today in strongish wind with a 4.5 m sail and results seemed good so far
75 MM tube squashed oval to give adjustable rake and welded in place over steering tube
Am now using centre sheeting Boom proved to be too weak and bent so I will need to stiffen that up
If I was building from scratch I probably would do it differently but this was an easy thing to do and seems to be worthwhile

Cheers Hiko