I reread this thread 'cause I did the same here with my A1000. I bought an A500 floppy drive to AmigaStore.eu (with the A500 button), made new holes in the bracket and sanded the button enough.
All seems to work perfectly, even with the front panel (the disk is recognized and it enters and goes out of the drive without problem), but when I close the A1000 and put the monitor on it, the drive works few minutes and after it gives me reading error, again and again...
Do you think it's a problem with the button ? Or maybe with the weight on the 1000 ?
I'll make test without monitor on the 1000, don't thought about it... and I'll test with the 1000 closed but without the button, I'll see !).
I saw I have a second "bracket/holder" around the original disk drive... I'll try to put it back too !
I hope to close permanently this A1000 soon
(even if I still have to solder the LED !