Need to mount your new tweeters on your 'A' pillar or window corner plate. but they just don't quite point to the right positions?
what you need is a Tweeter Pod to get that sound in the sweet spot for your system.

Print this inverted so the flare is at the top.
Only light infill is required 5% or so
Print in any resolution (finer will produce smoother blot up angle face)
pictures shown are only low res and printed in 30 mins including raft and support.
Printing with support will give a better flare finish.
You may need to glue your tweeter in place depending on it's mounting interface.