Okay, here comes George to trample on your dream.
I'll take a look at your screenplay. Though I know I won't finish it, as everyone else here has said. But, I think the reason why none of us will finish it, is because it's way too long. You know it's too long.
1. When modifying a screenplay you don't just remove scenes. If you wrote your screenplay properly using every scene to mean something in the story, character etc, it can't be removed. Something will lack story or character wise by removing scenes.
2. You say you just finished your first full length screenplay CONGRATULATIONS. Now, rewrite it. Every book, teacher or even myself knows that after you finish a screenplay walk away from it for at least 2 weeks (even better a month) try to get feedback (you're doing that here), and then take a close look at what you've written. The errors should be blaring, because you're not so involved in writing it anymore. (I've written things that I've gone back after a time, and have flat out said "this is complete shit").
3. If this is your first draft, it's probably all exposition, and pretty piss poor exposition. This goes along with #2, but it's something you'll notice.
4. If you're shooting in a month and a half, have no cast, and it's a 146 page first draft: You are setting yourself up for major headaches and disappointment. Unless you are the next David Lynch or John Waters (are you?) you have a billion to one shot of making something anyone will want to watch. (I know that sounds mean, but I don't mean it to. It's just the truth)
These are just some of the reasons why you are working too fast. Don't give up the dream. If it's micro-budget and you have no cast, then it's just a matter of time. So, hopefully time is on your side. If you do things correctly the outcome will be that much greater.
Now, one of the reasons your script might be 146 pages is because you're the Director and you've put in all the shots POV etc that extend a script's length. I don't know if you've done that, but if you have, it'll make it harder for me (at least) to read pertaining to the story etc.
Anyway
vanlutz@hotmail.com is my e-mail. If you want to send a PDF I'll give it a glance, and be beyond brutally honest. Just know this in advance; I firmly believe every story can work. I've yet to really see a movie where the story didn't work. Even the most boring movies I've seen the stories work. So, my notes won't be on story, it'll be on script writing.
One last thing (damn I write long posts) there's a reason why agents, studios won't accept scripts longer then 120 pages from novices. It's because it's almost impossible to get an audience to sit through a movie that's over 2 hours long. Even the most action packed adventure film's script is under 120 pages. You don't need 3 pages to describe a chase scene. So, 146 is way way too long.