To the OP: most of this has all been said, but as a fellow H-60 bubba (Navy side), it can be done. Don't give up your guard job, most operators appreciate the value of multi-crew experience in an advanced IFR helicopter (words directly out of an interviewers mouth). Don't bother getting a CFII-H unless the guard pays for it, and don't plan on using it unless you spend $$$$ to be legal in a Robinson or find a school that flies Schweizers. Finally, at ~600 hrs with 100 fixed wing, your best bet is just to get a CFII-Airplane. That will be you're fastest track to gaining hours, in addition to the valuable experience it provides and it's flexibility with Guard responsibilities.