i have a solid state dvr on my model 30 , fitted inside the toolbox ,works fine .
i have just put a new indian MCR2 regulator into my ariel NH , it works ok but the bullet connector sockets are smaller than original lucas and are made of steel , i drilled mine out to suit the connectors but i think possibly the new brass "classic" bullet connectors you can get may fit without mods but i havent measured any yet to determine this .