How to open older Electro-voice EV 630 mic ???

[studiodrum]

Hey guys,
Anyone have an older EV 630 or 635. I'm trying to open up the mic to take a look at the element and to clean up all the residual spit inide the grill. But, I'm not sure how to open up the grille?

I noticed that there were two screws on the side of the mic, but when I removed them, I couldnt remove the top grill, . .I didnt want to force anything so, Im wondering if anyone know how to remove the top part grill. . .
Thanks everyone

 

[normalizer]

does that button in the center of the capsule unscrew? that's how my 664 comes appart.

 

[shorttrack]

Serial number

Does anybody out there know of a link where I can type in the serial number of my EV 630 and see what is the history,i.e. date of manufacture?