Thank you for reading my questions. My bike has been sitting for <5 years and I want to get it (and me) back into shape.

I have a ~2000 Breezer Lightning I bought in college. I need to overhaul the drive train, I'm still on the first set of front and back rings. It is an 8x3 setup. I also need to get new Grip Shifts. My questions are:
1. I think I ned a H651 - 28T rear cassette, I"m going to the the CH HG71 chain as well. Is this a good choice?
2. Front chain rings, the big ring is printed Mega9 and the rings are stamped M9 N22, N32 and N44. I'm at a loss where to find replacement rings. I cant identify the exact model. Can someone suggest replacements?
3. I have not modified the bike in any way and again it has an 8 speed rear derailer and Grip Shift but my reading today says that Mega9 was for 9 speed derailers. Was is common or even okay to use an Mega 9 front rings with an 8 speed cassette? Will this cause chain problems?
4. Are Grip Shift 3.0 shifters most appropriate?

Thanks for your help.

I'm not a mechanic and some people will disagree :

It's safe to mix-and-match chains, cassettes, and chainrings within 1 speed of each other. I had a dumb bike with 10 speed chainrings, a 9 speed chain, and an 8 speed cassette. All of your choices are probably fine. The chainring you need is whatever roughly matches the one you have. I've had 8 speed chains on 10 speed chainrings, which is bad but I didn't think twice about it (probably wore out my chainrings faster than they should have).

The Grip shifter won't work if your rear derailleur is Shimano. Shimano and SRAM have different cable-pulls for their derailleurs. So look for a cheap Shimano compatible version. Ebay has great prices. Check "shimano trigger shifter 8 speed"

Chances are the rings are OK.
Some will have "altered" teeth to help assist shifting. Often they are mistaken as worn.
I'd replace the chain & cassette and see how it works.
IF it THEN skips on the front, replace the rings/crank.

For my money, nothing like a trigger shifter. I always hated those grip shifters and was stuck in the past with friction shifters until I got a Breezer with triggers. What a difference......instant and precise shifts.