Thanks Grumpy.
I ran the unit today for 30 to 40 minutes and it ran perfectly. Once done I drained the oil and added some replaced it with some fresh 30W Briggs oil. The choke I installed works nicely. It is interesting that I found the replacement carburettor is from a 12 HP OHV Tecumseh. It bolted straight up.
I'll get some pictures in the morning.