i know it had no detrimental effects on an old beetle engine if that helps!!! it wasn't a snorkel but the air intakes put into the rear wings (porsche911 style) woth a filter 1/2 way through then straight onto the carbs.
I would get an airbox from somewhere they must have some on flea bay, shame cos I chucked a load out a few weeks ago. I'll have a look if I've got anymore
id be putting an air box on there , put a free flow k and n and id assume you will have to re-set the pump timing to compensate.
im selling a disco one inc filter for a tenner but im not sure how far away from me you are.