5D and Pentax K adapter

Finally my Pentax K adapter arrived. Got out my Pentax 135mm 2.5 , fitted the adapter , tried to fit to the 5D - does not fit!
The diaphragm lever fouls the area under the mirror.
Checked on the 20D - no problems. (Same situation with the Pentax 50 1.4)

Anyone got any advice / info. I assume I will have to remove (pay somebody to remove) the diaphpragm lever, and possibly the metal around the lever (looks like a shroud to protect the lever)

Anybody know if these fit on a 1DMK2 without modifying the lens?

You should have been told (or checked before you bought) that the Pentax K to Canon adapter is only for APS-C (specifically EF-S fit - NOT 10D) size sensor bodies. It will not work with the 10D, FF or 1.3x bodies, as you have found the diaphragm lever on the lens catches on the mirror box - the EF-S body mirror boxes are recessed to take the extended rear of these lenses.

I think it's fairly simple to remove the lever. I have kept these lenses for over 20 years so I'm not worried about resale
Hopefully can get a good deal on getting a few done at once.

Which lenses are you going to adapt?
Some Pentax K lenses are very, very good and some, well aren't, at least not as good as modern Canon equivalents.
I also have an extensive Pentax outfit but wouldn't like the loss of AF on my Canon bodies just to use the K lenses - especially not to spend money on doing it.

I have 2 50mm 1.7 and a 50 1.4. The 50 1.7 was (and still is) one of the great Pentax lenses. Also a 135mm 2.5 which is really good to. A friend of mine with a 135 f2 Canon is very keen to compare. I got an adapter for him too , but he was aware of the lever removal requirement. He's got a Pentax 85 1.4 which is one fine lens!
Here's a pic taken with the 135 2.5.
https://photography-on-the.net/forum/showthre​ad.php?t=103467