Offset booster and master cylinder problems

I received the kit and after I had it mounted I looked in the master cylinder reservoir and to my surprise it had a coating of metal filings inside both reservoirs. I called and whoever I talked to sounded like it's no big deal... "just spray out the reservoirs with carb cleaner then flush the whole thing with brake fluid". I questioned his fix thinking there may be some filings already doing damage to the piston seals then he said I could return it if I wanted to but made it sound like it's a waste of time. I hear there is someone knowledgeable from CPP that checks this forum so I'm looking for a second opinion. I already tried his fix and now question if carb cleaner could have done damage to anything inside like the piston seals.

I was also very disappointed to find that although the parts list includes a "firewall seal", there is none. Just an open hole for hot or cold air to blow into the car.

What the tech instructed you to do is perfectly OK, but if you want to exchange it give us a call and we will be more than happy to exchange it for you.

Sorry for the late reply; if the master has any contaminants in it and you want to send it in for an exchange please feel free to email or call me directly with your invoice number.
The offset booster combination is so tight at the firewall with the offset design that there in no room for any type of seal.

Thanks and feel free to email or call me directly.