I had a hell of a time with mine. Thought maybe i had the wrong pads. Had use a large c-clamp on the caliper, carefully file the edge of the pad so it had a slight chamfer, swear alot, pry some more, swear some more, pound, hit pry, rant.....
They finally went together.
If/when you get em on, take a nice slow easy drive around the block and hit your brakes off and on. Sop and check how hot they're getting. Not too hot? Keep doing this for a couple miles. By then they should be seated/worn in enough. Mine still got a little warmer than usual for a couple days, but never warped the rotors.

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past MB rides:
'68 220D
'68 220D(another one)
'67 230
'84 SD
Current rides:
'06 Lexus RX330
'93 Ford F-250
'96 Corvette
'99 Polaris 700 RMK sled
2011 Polaris Assault
'86 Yamaha TT350(good 'ol thumper)