I finally(*) got a chance to fire up the Tektronix 566 that I purchased before Christmas. Here it is with eight independent traces on the screen (using two 1A4 four-channel plug-ins and independent time bases). It works like a champ. Now, as soon as I can get my 1L5 repaired, I'll be proudly replicating Figure 34 in App Note 35.
(*) Actually, I fired it up several weeks ago, but I didn't get a very good picture of it then.