hey man. you are tackling a pretty tough project. growing MJ, alone, with tons of light and space is much easier than smaller operations. In the case of a PC you can't get smaller. Things to consider are ventilation/air circluation, light, temp, soil, watering/nutes...To begin, and i think someone mentioned this already, you need sufficient light in order to produce buddage worth all the hasle you are going through. I reallly doin't think the 2 cfls are going to be enough in flower. However, adding more light is going to start messing with temps. A good way to manage this is add a makeshift cooltube. this can be done using a plexi glass sheet just below the lights, creating a barrier from the light and plants. If you add an exhaust at the top, and leave a gap in the plexi glass at the opposite end of the PC, you get your cooltube.
Next, by having constant air circulating, you are going to dry your soil quicker. Getting the biggest pots in there without wasting too much height can combat that. A great way is to use tupperwear that has been blacked out. You can find nice rectangular tupperwear to make pots out of and you will drastically increase soil volume.
Training the plant also needs to be happen. You can count on the plant at least doubling in height in flowering. If oyu dont train, you'll have to flower a plant that is only a few inches tall, and end with piddly little buds. Training can be done in multiple ways...LST, topping, scrog. Personally, to maximize quality buddage, i belive the scrog is the best method.
just a few things.
here is a link to my pc case grow i did a little while back. i vegged in my other box but flowered under a 70watt hps
https://www.rollitup.org/grow-journals/164898-pc-scrog-6-week-flower.html
i am so glad football has started again