Serial numbers were pressed into the rear of the removable lid of each CT-100. The number 605 appears on my set. --Pete

Below see a December 2001 photo of a CT-100 cabinet owned by Steve Kissinger. The rare, matching, 2-digit cabinet serial numbers of this CT-100 are shown on lid (upper) and cabinet.
Next, an Arpil 2002 picture of Terry Cheek's CT-100 lid and cabinet number 600. It comes from a Merrill whose chassis serial number is, like mine, below 1000. It's entirely possible that nearly 50 years ago these two cabinets, numbers 600 and 605, were within a few feet of each other at Bloomington.
June 2002. Here's the serial number on the nineteenth operational CT-100. In the collection of Terry Wise, whose caution to anyone restoring a CTC2 chassis is -- be sure to replace C107 (Sams) with a 1600-volt cap. A 600-volt orange drop will last a few hours then cause a loss of vertical sweep. [RETURN]