Removing fenders...at times the braces will break or the rivets come loose...and you don't want to see a fender coming off while underway. Fenders are nice and if yours, the OEM fenders, brace them good and do away with the rivets. There are aftermarket fenders out there that can hold up to the vibration of the engines.
On the choppers I have built, the chain will hit the fender....bench grinder takes care of this.
Kind of hard to see but I had to grind enough clearance for the chain.
As far as the engine tilt...what are you looking at? Yes some are tilted, in which case you might have to adjust the float.
As far as the chain guard, you need to mount the engine a little higher to clear the guard.
This was for a friend, and he wanted it this high, although I could of mounted the engine a little lower.
I wish I had a picture of the bike after he went home (150 miles away) and had pictures of the braces on his fenders. I wouldn't let him leave with the fenders on the bike.