I talked to the shop I got my system installed today and got basically the same song and dance. Apparently the old school pullouts had slightly oversized faces or some junk and didn't match up correct. They also went on that the sleds didn't conform to ISO din because they couldn't be mounted with the side mounting brakets that modern cars use. I won't know for sure if they'll actually be able to do it till I bring the unit in (Fedex says it's in town now, just waiting for delivery I guess)