I think there's a few similar threads that's been posted on here in the last decade or so - the search function will likely provide a gold mine of information.
Cliff notes "50,000ft overiew" version:
-Learn to ride in a fast bunch.
This will allow you to stay in first 1/3 at all times. Become comfortable with pedalling through corners such that scraping your pedal on the ground doesn't spook you. Become comfortable with being surrounded closely by people at speed and not have to keep looking at the back wheel in front - judge your distance to the riders bike by the distance to their body and not the bike - this way you can keep your head up and look for attacks or crashed and react in a timely manner.
-Since you're a skinny guy who may (or may not) lack explosive power then you'll rely more on your sustainable power to put the hurt on folks. Sustainable power is key to every cycling event bar track sprinting and I'm guessing there's a fair aerobic component to that. Read Andy Coggans pursuit prep - do a google search for "The individual pursuit: demands and preparation. Andrew R. Coggan". There's no short cut or magic 6 week program to racing glory but I do see plenty of sweat, pain, discomfort and lots of progress should you follow that plan. That said there's no 1 year program to racing glory either but you sure can make a lot of progress during that time. Don't try and short cut it by moving to the VO2 max prep unless you really have all the base (LT focus) of hard miles done already as you'll need that training and the adaptations it'll bring for the VO2 work to really shine. That document that Andy put together is probably a little overkill for what you're looking at right now and you could trim it down a bit but everything is there. Wednesdays session could go in or be trimmed down during the LT and VO2 phase, the weekends could be a little shorter but they are essential. The "specific" phase at the end could be tailored to include efforts on a short circuit (industrial park in the evening?) so you can do intervals on the road with corners included in the efforts.
Without the ability to put in a big 20 second effort that'll split the field you'll likely need to put in efforts more akin to a shortened version of a pursuit or a long Kilo. Find a tricky part of the course, go really really hard for 1 to 2km, see what, if any, carnage has been done and then do it again... and again... and again... and again until either you pop or the rest of the field does. The idea is string everyone out and hope that you force people to crack and leave gaps that those behind cannot close. Rinse and repeat.
- In training, remember to also train for things that people typically dont expect - people attacking through corners, attacking after the crest of a hill not just before it or on top of it. Get used to big efforts mid corner and hitting a big gear downhill by doing sprints in the biggest gear you can handle at speed going down hills similar to those you'll encounter during local races.
-Remember that bike racing is like poker on wheels.
He (or she) who shows his hand the least until it's "money time" often wins - translated, the fewer really hard efforts you need to make the fresher you'll likely be at the end. The winners often pedal hard the least. If you're not somewhat fresh in the last 1/4 and you've been sitting in then you're likely not trained enough to win. If you're the "new guy" who chases down all the breaks in the first 15 minutes then you'll be stuffed at the end. Since we're talking tactics start getting used to thinking "where is the wind coming from?" If you can mentally picture where you'd expect a rider to be drafting on your back wheel then you can picture where you'd need to ride in order to stuff them in the gutter unable to get a draft during your big efforts or to figure out where you need to be to get shelter from nearby buildings in a town center race. Going really really hard during a race and towing people around, unless you're actively working with folks in a break, is a really really dumb idea. Often the bunch follows "the racing line" for convenience or "just because that looks the correct line to take"... Maybe play devil's advocate if you find yourself on the front during the start of the race and take everyone down what looks like the correct line but in reality you'd want to be on the otherside of the road when attacking.
- Make sure your bike really does fit you and get used to riding in the drops or low on the brake hoods. Don't wear baggy clothes if you're at all serious about an event, skinsuits and the TT specific mitts are far more efficient. Get better tires and inflate them to the correct pressure. Use latex innertubes. If you don't need a bottle during the event, spend the 60 seconds to take the bottle cage off too.
There's lots and lots of stuff and the above is really just a few ideas of what to look for, how to think about what your training might look like (and how to avoid the common - i have an event in 3 weeks a 4 days and need to train for it - question) and a couple of hints and tips.