talking about 13b's here, which year model is most common for conversion? would asume the 13b from the second gen rx7 turbo 2 is probably the most common. but basically asking which side housings are mostly being used. would think the 4 port side housings. haven't got my rotary conversion manual yet but have read whats involved. anyone have definate answers on the differences in models and years of the different side ports.