Small Engines (Lawn Mowers, etc.): Engine swap out, craftsman dlt 3000, briggs and stratton

Question
David,
I bought a used Craftsman DLT 3000 mower for $150 that has a blown motor (turns out the exhaust valve broke off and banged around in the cylinder, destroying the head and piston). It came with a Briggs and Stratton 18.5HP Intek-Plus motor (31P777-0296-E1). A new cylinder head, valves, piston and gasket will cost about $300, which is what I expected. Here is the question, I found a couple of new motors online for about $500, but none of them are exactly the same model, but all of them look the same and seem to have the same bolt up patterns from the pictures, and all of them seem to have the same size crank. Specifically, the closest I found is a 31P777-0492. I was wondering will this engine work? For the life of me, I can't see why not, and its not much more money. Will any B&S motor work if the crank and bolt up pattern is the same? I also found a B&S 20HP motor for a John Deere, but it looks like it would bolt up also. Thanks for all your help.
-Neil

Answer
Neil:

The bolt up should be the same.  Make sure that the crankshaft length is the same.  

The main differences will be charging system, cable controls, perhaps oil filter, etc.  

you can exchange parts off of the broken engine to make the replacement engine work if need be.

Happy Wrenching