I was off the beam, looking for word pairs. Came up with AUTOBAHN and TINY45AVery small[----] STEP58DPart of a process[----], but wasn't getting much further.
I thus needed the first three nudges to find the right coupling, though two might have been enough if I'd been more patient. (I backsolved for the "I" and thus didn't need the last nudge). Very clever disguising.