spliting a super-c

Whatever you do, make sure it has wheels. The simplest stand is two vertical channels with an axle as Hugh described. Simplest is often the best solution.

The wheels should have a wide track, at least 4' to provide stability to the tractor. Add cross-bracing so the stand doesn't collapse.

A stand like this will work for both wide and narrow fronts. Wedging the wide front is good insurance, but not necessary with a sturdy wide-track splitting stand under the rear.

On wide front tractors I use a hardwood pallet with blocking, under each side on front axle and under back of engine. I use tiedown straps, tie it solid to pallet. Put wedges in front axle pivot. With a C-123 engine I built a wooden cradle so edges of block take weight. I use a bottle jack under clutch housing and a pallet jack to move the front end on the pallet. I have split tractors as large as 560 and put them back together using this system all by myself. I've also split a big articulated tractor at the pivot, removing the whole rear end with wheels, on a pallet.