Do I have to put the ignition interlock system in my car

It depends on your DMV's authority as well as on what happened in court. In Wisconsin the DMV can apply administrative sanctions commensurate with its records. Also, Wisconsin courts often order an IID for first offenders. I would suggest talking with the lawyer who handled your cases and probably managed to keep you out of jail.

Who is telling you you have to do this? Probation? If they are truly first offenses each then there is no requirment that you have the ignition interlock but I can see probation possibly making it a requirment.

Unfortunately you have been caught in the rarely understood limbo between PennDOT's civil authority and the criminal court's criminal authority. It is a trap for the unwary. In a decision of Smith v. PennDOT, 41 A.3d 924 (2011), the Commonwealth Court held that, in situations such as yours, it is proper to impose an ignition interlock requirement. Although the criminal courts treated your charges as two 1st offenses, the civil authority of PennDOT treated your first offense as a "prior offense" and imposed the ignition interlock requirement to your second 1st offense. You should have received notice, in 2010 of the suspension as well as the requirements for restoration. At that time, you would have had 30 days to file an appeal. However, if you would have filed an appeal at that time, your appeal would have been unsuccessful. Since you did not file a timely appeal, the attorneys at PennDOT will vigorously oppose any attempt to appeal the decision now.

The offenses were first offenses for mandatory sentencing purposes but they are two offenses, which requires installation of ignition interlock under Pennsylvania Law.