Just finished putting a kit on the rear caliper, went to install but am having a hell of a time getting the pads to fit with the shims in place. 

Without the shims the pads drop into place as intended, with the shims placed in position the pads just don't want to fit easily. 

Everything is stock. Watched a Youtube video of the same pads and the pads just dropped into place with shims installed. https://www.youtube.com/watch?v=9KSBjRMoHF0

Mine won't do that, very fkn annoying. 

any ideas or tips would be appreciated. 

Sorry can't add more.

No mate, the piston is not the issue. It's the overall dimensions (L & W) of the brake pad that is the issue. I checked the new pads with the old and the new ones are about 1mm bigger in width more so at the internal 'hooks', just enough to stop them going in as intended. That's what you get with aftermarket stuff I guess.

 

I spoke with an old mate who used to have his own shop back in the day, he said to take a dremel and slowly shave off enough for the pad to fit. 

So taking a smidgen at a time I shaved them back and now they fit. 

Brakes are working fine now.

Now I'm up for a new rear brake light switch as the old one has gone south. I'm wondering if I did some minor damage whilst blowing air through the master, I did that multiple times on all parts as I read that you must keep everything spotless with no foreign stuff anywhere. No biggy, a brake light is a must these days especially with all the f/w on their phones. 

Cheers