yes works great - fitting in a box, when you build the kit there ia a large transistor that the heat sink bolts to - its a case of cutting a smallish hole in the box lid so that the heat sink is fixed to the box lid then the PCB is bolted on the back of the lid making good contact with the heat sink if you use a metal box it becomes the heatsink - but they dont get in the slightest bit warm on a 2cv so pretty sure you could do without the heatsink.
they dont work when they get wet so site it away from any splash zone. my car is just "switch on switch off" no cranking necessary unless its the first start of the day.
however as its a DIY kit its the skills of the maker that determine the outcome

SAM stick it in the Mehari and ill fit it at some point

ps yes Geo ill come and speak to you about 12spark in Spain

Thanks for the info. Isn't the metal tab of the transistor supposed to be in good thermal contact, but electrically insulated from, the heatsink? To my mind this would require a much bigger hole. And where did you put the box, on the bulkhead?

Spot the transistor and heat sink...

http://www.ebay.co.uk/itm/Ignition-Module-for-Talbot-Solara-1-3-1-5-1-6-1979-85-replaces-Chrysler-3874020-/330643975640?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item4cfbeaadd8&nma=true&si=VCqMpJ8bwCtR%252FB6mKtyfjXzkZBk%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

i cut a square hole the same size as the base of the transistor bolt it tight to ther heatsink through the lid then screw lid down and finally pop rivet heatsink to lid - the box is the same size as the heatsink

you could try potting it

Just fit a 1-2 sprak and forget about it.......