Could not locate assy manual, but found in old parts books I have that Chevy used the same cross members up front, within each series of trucks. Example 54-55 1st series cross member/'eng support' is same part for 1/2 & 3/4 tons. FYI group # 7.229 part 3703340.
Chevy also used same part 1/2-3/4 'engine support' from 37-42(46) #594034.
And,for 47-53s both used gr 7.229 #3683311.
The frame info for 53 shows heavier channel matterial for 3/4 tons and very slightly larger in dimension, but front first two cross members appear still to be the same.
Final note, this parts is referred to as 'engine rear support' not cross member.
Hope this helps someone.
