Massive detabbing of the source

I thought I could clean up the source code from all the tabs and then remove {-# OPTIONS -fno-warn-tabs #-} pragmas + comment below it. This is a massive change though (140 files would be affected) and I suspect it could potentially be a problem to others working on the source (could cause some merge problems). So, can I just proceed with cleaning up all those 140 files and then send a single patch or should I devide this task into smaller ones (e.g. a single patch for every directory in the $(TOP)/compiler/) or should I just give up on this idea? Janek