Hi Tony, you have a right to be confused, I'll attempt to explain the situation clearly to everyone!
McLaren No. 1652 was built in 1919 and is currently owned by Les Searle of Horsham, West Sussex. Most people will recognize the engine by its preservation name "Boadicea" and in the configuration shown below:
During its working life, No. 1652 "Boadicea" was owned by a showman who converted the engine to showman's specification ad re-named the engine "Gigantic", however these fittings were only carried for a year or so as the engine was found to be too heavy for use on fairgrounds.
In 2013, the current owner, Les Searle, decided to temporarily recreate the long lost showman's fittings for a bit of fun and fitted them to the engine, also re-instating its showman's name "Gigantic". And so in late 2013 the very same engine as pictured above looked like this:
Les has now removed these fittings and so currently the engine is back to normal, once again being named "Boadicea" and looking like the first image.
Now then, there is a separate engine, No. 1332 of 1912 which rather confusingly is also called "Gigantic". To make matters worse, this engine is exactly the same design as No. 1652 "Boadicea". "Gigantic" is pictured below:
This engine is owned by Neil Gough, also of West Sussex, who is currently re-building the engine and it is this engine that is being re-built into WD specification and is planned to attend the Brighton Run, not "Boadicea".
Hope this helps!