Leaving in 1 month and 25 days.

First of all I want to thank everyone for all of the information that they have provided in the threads. I have religiously read every thread that has been posted on this site and have soaked in everything that has been said. I appreciate everyones helpfulness and encouragement.
Now down to bussiness... I am a 21 year old guy that had to drop out of school and playing football for the University of Arkansas a year ago, to take up a job and start working to help out my family because of certain financial situations. Seven months ago I was living a crappy life of working nights, eating because I was bored, and sleeping. Until one day I woke up and was like what the hell am i doing!! So then I decided to start trying to accomplish my childhood dream of becoming a United States Marine. Like I was saying, seven months ago I weighed 335 - 340 lbs (football coaches like that) and stood 73 inches. Now I've dropped down to 239 lbs and am in the best shape of my life!! Now the problem is that Im scheduled to ship to MCRD San Diego on 20080220 and still am a sort of a fatbody. Due to playing football all my life and only using certain muscle groups that are worked and required to use as an offensive lineman, I kinda suck at running and pullups. I can do more than the mininum chruches for the IST and I can do pushups all day long, its just that im really worried about my running and pull ups. Ive been jogging/walking 6 miles a day for about a month now, and I can only do one and a half pull ups. So as you can see I have a problem, so any information would be much appreciated! The other question is that during boot camp, am I going to be picked on more because of my size or will it be to somewhat of an advantage? All my recruiters tell me that im going to be fine, but im just a little worried that my boot camp experience is probably going to be a little more difficult for a guy like me. Haha! Anyways, any information that you guy's could provide would be much appreciated!!
By the way, just to let ya'll know, there is nothing that anyone could say or do that could deffer me from earning that title! I have been wanting this and dreaming of this for so long that its almost unbelievable that im only a month and 25 days from starting my dream!! And nothing is going to stop me now that im this close! Thanks again everyone!