The bonnet catches on those are renowned for breaking. The same happens with similar age lagunas. The only solution is a new bonnet catch, either from scrapyard or a parts supplier. The bonnet pull cable connects to one of the latches, which then has another cable coming out of it to the other latch. I did one on a laguna, and it was a bit of a mission, but it is doable.
John
March 2008