It's a socketed replacement in the SE and Mac II. i.e., they sold 800K floppy equipped IIs and SEs which were later upgradeable to 1.44 floppy operation by swapping the IWM for a SWIM and changing the ROM chips.
That suggests that the two are pin compatible, unless the SWIM has more pins and the two Macs were built with a longer socket with upgrades in mind, but that seems unlikely.