I think this picture that Dave posted of the right side of Rotary 2 and the pic in the pictorial, captioned as in Skagway, of the left side are the best example of rotaries 1 & 2 (OM & ON)as delivered.
Not counting the 6 rotaries built buy the Canadian Pacific in 1888, Cooke built the first 28 rotaries. The first 11 all seem to have the low body identified by the steam dome protuding higher than the roof line. Early pictures of Colorado Midland 08 (A) show this body style.
Starting with Rotary #12 for the Omaha Rd, pictures show up of a taller body identical to those early D&RG 2 pictures, Mallory Hope Ferrell had a great picture of The C&S 99200 (Cooke #26) as delivered in UP lettering in his SOuth Park book. This body seems to be a bit of a standard built as an option to the low body. This body seems to show up on quite a few rotaries such as #11 (Omaha Rd R50), #13 (CNW A), #14 (CNW
, #16 (AT&SF 99801), #17 (CM&Sp 2), #23 (DSS&A 711), #25 (DRG 2), #26 (C&S 99200), #38 (Rock Island 95357)
This list uses more modern numberings which are more recognizable instead of #16 (Chicago, Santa Fe & California) which became AT&SF 99801.
Many of these taller bodies must not have given enough head room or visibility in the operator cabin area as many of them had extended roofs over this area like the D&RG 2, The Rock Island, Omaha Rd, and the C&NW all extended them. Some of these extensions were pretty crude.