X5 wont start----HELP

[ArtMan]

Ok

Long story short: took tranny out rebuilt it put it back in has some minor issues: during that time it started up just fine with the old battery which had drained completely and i charged it back up and it fired her up no problems. So i had some minor issues so retook out the transmission checked some things put it back in and charged battery again and nothing...so i assumed maybe not enough charge or amps to crank so i put in a "new" same battery from my dads van (sprinter uses identical battery) which was just replaced so its new maybe 5 months old....and again nothing...

now all lights come on every thing works but it wont even try to crank its like turn key all lights on key goes all the way to the end and nothing no sound nothing.....

My dad was saying maybe when i reinstalled the started i didnt line up the teeth right and it might not be able to turn but then i put started last and it slide right into its spot and i had no issues there....


please any one any suggestions are welcome....help me brainstorm!!!!