Ok, first of all the boosters need to be thinner. 1.6m, yours are 3m wide (twice as much). They should also be 17m or 20m tall (without the nosecones), depends if you use aj-60 or gem-63 (I'd suggest the latter, is the current configuration)
Now for the core, it should be 3.8 metres wide. (You can round up to 4). It also gets narrower at the end, so probably a 3.4m fairing there. If you want the frontiers to look good in such a configuration, either stack them (side view) or make them narrower with BP edit. Your fairing is too wide, should use the standard 5.4m fairing. I'll add more details later