How to run two Postdoctoral fellowships at the same time? I have recently applied for two different Postdoctoral fellowships in the same host group and I got both of them. My host is very happy and suggests me to run both of them at the same time. However, there are some administration details that are not clear to me at all. For example, will the fellowship foundation be happy to known that I will be running another fellowship at the same time? 

My current plan is to ask one of the foundation (I) to fund a technician and I could still ask the foundation II to support my own salary. In this case, I think I will definitely need to negotiate with foundation I because the change of personnel. Question is that how should I inform foundation II? In fact nothing is changed here, I feel like I am looking for troubles if I simply inform them (foundation II) that I got another funding to support a technician. 

Your ideas/experiences about how to handle this situation will be greatly appreciated.
Generally foundations "request" that you inform them if you receive extra funding for the same budget. They probably expect that you apply to several foundations simultaneously. However, if you negotiate with foundation I to change the scope of the funding (such that it doesn't go towards your salary, which is presumably already covered by foundation II), then I think you're in the clear.

Alternatively, if foundation II didn't fund your full budget, then you could accept part of the funds from foundation I to cover the remaining costs, then inform both foundations of the arrangement. That should also be uncontroversial.