So I got another box from Shapeways this week, so I decided to get a bit more work done on Rotorstorm and Hurricane. Here are the results;
Those plates have a %mm port for the guns to plug in in helicopter mode....
....and form a possible arm cannon for robot mode. (Note I'm just using MW Sandstorm's guns as a placeholder)
Hurricane's engine plugs into the tabs for the original engine from Sunstreaker/Sideswipe/Red Alert....
...and becomes a weapon...duh
