Oh - and by the way - if you're still gaining nicely I'd keep running with it. I also wouldn't diet down to a particular number. Unless you have your nutrition down to a science - numbers on the scale can be a bit misleading. If you just feel the need to get leaner then find out your true body fat percentage then diet down to a smaller one. The goal is not to loose weight - but to loose fat. Since you're so new to the game it's likely that adjustments to your nutrition (frequency, quantity and quality of meals) may allow you to continue gaining LBM weight while leaning out.
IMO - the best way for you to lean out at this point would be to keep your calories relatively high and add more cardio. Keeping your calories high will allow you to continue to lift heavy therefore retaining (and even continuing to build) that beautiful LBM which will burn off the fat.
A lot of guys new to the sport make the mistake of dropping their calories too much and burning off a bunch of their hard earned muscle. They tend to get smaller and lighter but not much harder. In other words they become smaller versions of themselves.
Yeah - like someone else mentioned - check out the nutrition section in here - it's full of great info.
My 2 cents,
Chuck