Some have reported that a 52mm filter will push inside the lens body and be a nice tight fit, but it does not actually screw in and is just a friction fit. The lens appears to be a 55mm thread, but the 55mm Hoya filters will not screw in because the filter threads do not extend deep enough into the lens. Pretty sure a 58mm will NOT fit, sorry, but you could always tape it in place. I will be setting up my IMX lens later this week. 55mm to 67mm step up ring (which I may have to glue to the lens), 67mm Hoya HMC FL-D filter, 67mm to 95mm step up ring, and an IMX lens. It won't be pretty to look at, that's for sure.
Anyone else think that the projector body gets damn hot over the location of the bulb? I may just place a large metal heatsink on the top of the case and see if that helps. The heat does seem to be only in the bulb area though, so maybe I should just forget about it.