NA MX5 headlight retaining screw size

Are the 3 screws used to set the 7" headlights in place m4 screws?

I am changing my headlamps to Lucas 328 units, one of the screws was rounded. While I managed to get it out, the others are all pretty rusty, so I want to change to stainless screws.

I know MX5parts and Autolinkuk have new/used Mazda screws, but I refuse on principal to pay £1.19 and 60p, plus post for a new or used tiny screw, when I can get a pack of 10 shiney stainless steel ones delivered to me, next day free, for £3.

From memory think I used M5 when I changed a headlight but they were in my “bits” box…

They were M4, but the rounded off screw seems to have opened up the hole slightly; the screws just turn into sheet metal, so debating where to put in a self tapper. Put in new stainless steel screws, but one isn’t tightening.

This all started from a loss of main beam on one side. The assumption was a new set of bulbs was needed , and a set of Philips RacingVision 150s were ordered. The Freeform headlamps were fittedabout 10-12 years ago, to replaced a cracked Wipac unit. They are un randed, and in the intervening years, the polycarbonate has taken a beating (lots of scratches) and the rubber boots are shredded

I’ve taken a decision to go back to decent quality old school glass headlamps, and went for Lucas LUB328s



However, after fitted the new lamps and bulbs, it seems to original issue may have been due to a bad headlamp socket. Both sides are quite corroded (verdigris). Now do I spend time trying to clean these up, or do I fit new sockets. I have a pair of ceramic Ring H4 connectors; to fit, I need to snip the wiring, and connect with bullet connectors. Bit of a one way exercise.