Yes I have in fact done the power button. Took me some time (4-5 hours) but I was enjoying it and very carefully wired up everything with insulation etc. I always want my work tip top. My opinion? Well worth the work!! I've had it for quite a while now and still love it to bits. My favorite Mod

If you are interested in doing it, don't purchase those instructions as there are very good instructions online which you can use. Also, there is a Ford Power button(Like the one the new mondeo has) which lights up really nice as opposed to that shavvy red button
if you need any more help and opinion don't hesitate to ask =)