Perhaps a FSDO question but thought I'd try here
 

If you are JAA private and have converted your JAA to FAA License(private). The FAA lic states your JAA lic must be present to utilize FAA lic. So basically it's not a stand alone FAA private lic.

Can a person above train in the States and apply for FAA Instrument? Or does this person need to make his FAA lic stand alone first before applying for Instrument?

Thanks!

I have a friend who has flown airlines and corporate, and her PPL has always been based on her foriegn license. Of course she has a US commercial and IR, but I think she had foriegn licenses when she arrived, and just took all the US checkrides.

Since you want to train based on a foriegn PPL, better ask the feds. I suspect you can.