Gonna try to install one of my 2x new SMC units...

[Igofar]

There is an article that @Mellow posted years ago to guide you on the piston cleaning job.

They should look like this when you are done. I extended my pistons before returning them to this position after cleaning. When returning pads to the caliper, ensure that the right pad is set inside the two pins that are circled on the spring clip. As well the clip at the back of the caliper must be cleaned and the pads must straddle the center bar of the clip in order for the pads to move freely with the caliper. Last pic was meant to show the straddle. Thought I had a better one.
View attachment 334779View attachment 334780View attachment 334781View attachment 334782

FYI your 3rd picture (rear caliper mounting bracket ) appears to have quite a bit of wear on it.
There should be ZERO gap between the steel clip, and the aluminum bracket. When that gap starts appearing, it allows the bracket to shift around and start binding things.
Just saying….

 

[Igofar]

This is what clean should look like, and yes, a bent or dislodged clip can damage a piston if it’s not seated squarely.

 

[SMSW]

This is what clean should look like, and yes, a bent or dislodged clip can damage a piston if it’s not seated squarely.

Larry, in post #159, Dk Shad's third picture shows a tapered, worn brake pad. Is that bad enough to require changing? Could it be the cause of some of his woes?

Were this my bike, I'd probably change the pads at this point because I'd most likely be doing the work during our winter, and I tend to budget $$ ahead for maintenance. Uneven wear bothers me because I take it as a sign something is hanging up somewhere and something needs attention. I understand Dk Shad has limited funds for these things, so if you think he can get away with the worn pad, that is probably the route he will take.

 

[Igofar]

If you’re referring to the last picture, that would be on the wrong side, so it’s my guess, that it is just a shadow.
But in answer to your questions, yes, crooked pads point to something not working correctly.

 

[jfheath]

Just clarifying about those tags on the pad spring. It's actually quite difficult to get this wrong with brand new pads, but with older pads it is a distinct possibility.

This is what the pads look like in the correct position when the caliper is separated.

The sure-fire way of getting them on the correct side, is to pull the caliper towards you as you slide the inner pad (shown) into position - so that the pad is squeezed between the caliper and the brake disc.




Also

That spring clip shown in photo #2 of Igofar's post - 3 up from this one - is supposed to be glued into position so that it is less likely to vibrate and wear its housing. It doesn't need the adhesive - but the glue puts a layer between the two metals preventing one from wearing the other away. The only place that this is mentioned is in the table of lubricants in the workshop manual. They recommend Threebond 1521. I found a more readily available alternative - UHU Max Repair Extreme. Similar properties - flexible polymer, high pressure higher heat rating than 3-bond. Just checkled the UHU site. UHU Max Repair Power seems to be an updated version.