Did some further research as promised in the 1954 Factory Assembly Manual. A few observations and questions. First there are as you know many references in the cab section to LD/RD and LH/RH instructions. As Tim stated there is no plate detail for 54' RH posts which leads to several questions. I know and others have stated we have the holes on the RH side of trucks from 1947-1950. Further these holes are exactly the same as the ID plate. So guys with 51-53 trucks do you have similar? Was a change made when the ID plate went from screws to rivets? In the Assembly Manual there are some interesting plates see pictures below.
http://www.flickr.com/photos/advance-design_parts_co/10713929785/http://www.flickr.com/photos/advance-design_parts_co/10714019966/LD cabs show the new updated wiper bracket while RD cabs show the previous 47-53 style why? This theme continues to the dash
http://www.flickr.com/photos/advance-design_parts_co/10714004914/http://www.flickr.com/photos/advance-design_parts_co/10714208693/RD cabs are shown as the older style while LD cabs are shown as the new 54 style. The dates are from June of 1953 so they are not earlier versions. Again why? Was GM still constructing this style of truck for RD markets? So more questions than answers but it is interesting stuff.
I posted earlier on Australian market RH trucks here is a brochure for RH South African trucks.
http://www.flickr.com/photos/advance-design_parts_co/10252652294/
