No I did not put cross overs on them because most tweeters are now made with built in cross overs.
I have a picture of a metal braket screwed in there. You can do that or just simply place the tweeter on the center of the stock 3.5 speaker. You won't see a tweeter in the picture because I blew it. They were dirt cheap nonames. I'm going to be upgrading everything to Pioneer.
Just Google "Pioneer hard and soft dome tweeters". Hard for the harsh sound and soft for the smooth crisp sound. They will both be crisp either way.
Trust me, you will love the sound. 3.5 speakers are a waste.