Not going to happen, unfortunately. ALL PCMCIA USB cards require CardBus, and unfortunately unlike the 2400 and 3400, there is no way that the 1400 can be modified to take CardBus cards, as its based on a NuBus architecture unlike the others.

Sorry to be the bearer of bad news - as a fellow 1400 owner, I'd love the ability to use USB devices, mostly my USB drives with my 1400, but sadly it just ain't gonna happen.