Small Engines (Lawn Mowers, etc.): Replace engine, custom muffler, craftsman model

Question
Thanks for the answer to my previous question. I tried to respond to you, but you were maxed out. I bought the new engine, and it fits ok. the electrical connections look like they will just plug and go, and the throttle doesn't appear to be a problem either. The muffler looks like the same one they use on the new tractors with v-twin engines, so all I need to find is the correct header pipes. Can you help me to find what part number to order? The model number for the engine is Briggs 40G7770123. The tractor I'm putting it in is a 2000 Craftsman model #917270930. The original engine was an opposed twin model #4617070145E3.

Answer
Take a look at the site below and see if anything might work.

http://www.brandnewengines.com/enginemufflers.aspx

You might want to check around local area mower shops and see if they might have a used muffler that you can buy cheap just to use as a donor muffler for the headers.  Then you can make a custom muffler if you have a MIG welder.  I would also check Ebay for cheap used mufflers.

Eric