Albert Barnes Commentary 1 Kings 7:36

"And on the plates of the stays thereof, and on the panels thereof, he graved cherubim, lions, and palm-trees, according to the space of each, with wreaths round about." — 1 Kings 7:36 (ASV)

According to the proportion of every one - that is, “as large as the room left for them allowed,” implying that the panels were smaller than those on the sides of the base and allowed limited room for the representations.