If you want more stability, weld a big plate (probably 1/4" or so thick, at least 12" square) to the bottom "foot" of the stand, centered. That will make it MUCH harder to tip!
However, I've been using 2-ton stands for years - sometimes even putting "all four paws in the air," without incident, the saddle on them is about 3" wide. I may eventually make "socket adapters" to go on the ram/saddle to give enough width for the frame rail, but I haven't bothered to design them yet (or get some bar stock and machine out new rams, with wide saddles...)
"recon" (sic - reckon)(tm) "hihgly"(tm) "seceed"(tm)
"Outback AIDS - Alcohol-Induced Dizzy Spells"