Here is my 1974 Groundsmaster 72 after I rebuilt the mower deck.  The four cylinder Continental engine is still running strong.

The only engine work I did was replace all of the electrical components.  Plugs, wires, points, condenser, distributor cap, etc.

Here is how the 72 looked when I bought it.  The deck was rough.

The deck was missing a spindle bearing, and had huge rust holes in it.  I ended up welding about 30 lbs of steel back into deck to get it solid again.  That is a lot of steel.