You will need to do the CPL and IR written exams. The three hours training for CPL and the three hours for IR with an FAA CFII and then sit the two check rides with a DPE.
The IFP does not grant IR privileges to a full FAA certificate only a 61.75.
So if you want a full FAA CPL/IR, you jump through the hoops. Luckily the FAA are pragmatic enough to give you full credit for prior experience and only mandate minimum requirements as outlined above.