These are small salads, more of an amuse-bouche, but I like the look of all single digits on a sign assembly. Large ones are obviously rare, but there must be others with 3 or more routes.
Here's what I've found in Connecticut:
(https://i.imgur.com/FWkPNQk.png)
(https://i.imgur.com/dbPHYor.png)
(https://i.imgur.com/3ggFQ9B.png)
Kinda-sorta salad, if you include the mileage:
(https://live.staticflickr.com/8525/29511971766_3229cf0f28_b.jpg) (https://flic.kr/p/LXSz2q)
Utica, if we're allowing suffixes:
(https://live.staticflickr.com/1746/42805916581_5d15f59079_b.jpg) (https://flic.kr/p/28dBvEv)
Heh. Just saw a CT 2/CT 5 sign in the construction zone on CT 15/US 5 near I-84. Sorry, no picture.
MD 2-4 in Calvert County MD (https://www.google.com/maps/@38.3887243,-76.4360131,3a,43.2y,12.09h,88.29t/data=!3m6!1e1!3m4!1syYUUlSZlgjrzDlI9w3yusg!2e0!7i16384!8i8192!5m1!1e1?hl=en)
(https://live.staticflickr.com/8079/8345500273_88246e7edf_z.jpg) (https://flic.kr/p/dHsStK)Vintage photos from 2001 - 064 (https://flic.kr/p/dHsStK) by H.B. Elkins (https://www.flickr.com/photos/hbelkins/), on Flickr
(https://live.staticflickr.com/8215/8346557056_aac543f925_z.jpg) (https://flic.kr/p/dHyhC9)Vintage photos from 2001 - 089 (https://flic.kr/p/dHyhC9) by H.B. Elkins (https://www.flickr.com/photos/hbelkins/), on Flickr
5 and 10 in Los Angeles because of the East Los Angeles Interchange.
5 and 8 in San Diego.
1 and 2 in the Santa Monica area.
North of Yukon, Oklahoma:
(https://live.staticflickr.com/4825/46631861292_5149b44182_b.jpg) (https://flic.kr/p/2e3GtJu)
Calhoun, Mississippi:
(https://live.staticflickr.com/952/26815700177_d55a81a3eb_b.jpg) (https://flic.kr/p/GRBtqe)
US5 and US2 on a stick in St. Johnsbury, VT
(https://live.staticflickr.com/1670/25922075732_b8a9424558_c.jpg) (https://flic.kr/p/FuDq1d)
IMG_2698 (https://flic.kr/p/FuDq1d) by Paul Drives (https://www.flickr.com/photos/138603251@N02/), on Flickr
1 and 5 on PEI:
(https://live.staticflickr.com/65535/48829298938_c804bc906b_c.jpg) (https://flic.kr/p/2hoSVos)
IMG_4311 (https://flic.kr/p/2hoSVos) by Paul Drives (https://www.flickr.com/photos/138603251@N02/), on Flickr
A BGS in Nova Scotia that isn't technically multiple panels, but might hit the spot:
(https://live.staticflickr.com/65535/48818312497_e0baebd8d7_c.jpg) (https://flic.kr/p/2hnUBv4)
IMG_4138 (https://flic.kr/p/2hnUBv4) by Paul Drives (https://www.flickr.com/photos/138603251@N02/), on Flickr