Rear brake pads, wrong part?

I can't seem to get by new pads on my '92 F2. Not enough space it seems. I have tried putting them on with the old pieces that were on the old pads and that makes everything way too thick to go into the allocated space. The parts that came off the old pads have a fiberglass looking piece then a stainless steel?, spring steel? backing plate. What's up?

Thanks for the new hat, site sponsor! Cool hat.

Got it! The piston? thingy didn't look like it would move this afternoon, so I looked elsewhere. I just went out and moved it with my fingers. Great. I had to put some Channel Loc type pliers on it to finish squeezing it in all the way. Worked great. Got my new pads in, in about 15 minutes.

yup... collapse the pisstonz

Did you take the lid off the brake master cylinder first? Cos if you didn`t you may have pushed air into your fluid.

No. Air? From whence would it come? I was thinking it would push fluid back into the reservoir is all. Do I need to bleed the system now? It's bad enough that one bike is down, not another!