60psi of static fuel pressure is a bit much, considering spec is 30-40. Again, static fuel pressure is with the vacuum hose OFF the regulator so that it sees atmospheric pressure. If you start with a given static FP, once you boost, your FP should be rising above that number if your boost dependent FMU is working right. The 124psi I was talking about was if you are running 40psi static FP, and had a 12:1 FMU on 7lbs of boost(7 x 12 + 40). Yes, this IS a high amount of fuel pressure under boost, but that is the drawback of FMU fuel setups. If you plan to run high boost, then you're generally prepared to invest in better ways of handling fuel, but for lower boost levels, an FMU setup is fine, which is why a lot of kits (DRAG, REVhard, GReddy, etc) include an FMU to add fuel for their kits, which are designed with lower boost levels in mind. Again, if you do not have an inline pump, you will never see these kind of fuel pressures since an intank pump cannot produce that much pressure.

So, either your FMU is not fuctioning properly, or your intank pump is not putting out enough pressure to allow it to do so. In either case, that would explain why you're fuel pressure is not going beyond 60psi or so. Try setting your static FP to around 40psi and make another run with your buddy hanging out the window(never thought I'd be telling someone to do that...) and see if your fuel pressure rises beyond 40psi under boost. If it does then you're FMU is fine, but your pump can't supply the pressure needed to raise the FP further, if it doesn't go past 40psi, then your FMU is not working properly. If it goes up to 45-47psi or so, then what you have is a 1:1 rising rate regulator(raises FP 1psi per every 1lb of boost), and not a boost dependent FMU.

You can run a check valve for the MAP and get 310s, and they should be able to idle on your stock ECM, but you'll probably be running pretty rich. If you did that, you could probably play with your static FP to get it to run pretty decent, without an FMU. Yes, you could get an AFC or other piggy back fuel controller to fine tune it, but it's not absolutely necessary.

Or, you could run check valves, keep your stock injectors, run a 12:1 FMU(or get your existing FMU to raise FP 12lbs per 1lb of boost), and an inline pump. This should also run a bit rich, but only under boost, since the FMU is only raising FP under boost. Oh, and your FP will also be pretty high under boost as I have explained. You can add a fuel controller to this setup as well, if you want to fine tune your fuel map under boost.

In either case, you would need to get rid of the GReddy box. If you choose to go with larger injectors, then your high-flow intank pump should be more than up to the task, but if you plan on using(or continuing to use) an FMU setup, an inline pump is crucial in order to provide the high fuel pressure an FMU needs.