Jo's is the double version of yours with two pairs of tandem cylinders side by side ( 4 cylinders total). The two models share a lot of the same parts so Jo's build and comments apply to your engine
Yours is at the top of this page hers just below.
Here is one half of Jo's which is basically what your engine will look like
J
Edited By JasonB on 02/08/2013 20:19:00