My blazer is nearing 15,000km (2005, 2-door), my mechanic told me that now would be a good time to apply some dielectric silicon grease to the brakes. I have the Helm service manual, it lists everything you could possibly want to know about the braking system except how to maintain them.

So where specifically should I apply the grease?

I'd also like to lube the chassis while I at it, I was told there's about 12 or 13 points that need greasing but again the service manual doesn't specify where.

I think that BlazerLT answered both questions best

brake info here
http://www.automotiveforums.com/vbulletin/showthread.php?t=564633

I can't find his grease nipple thread, but if you take a good hard look you'll find more than the lube shops do