How clear are you on your outcome?
If I read what you wrote literally then your primary problem is lack of time and lack of resources. Can you renegotiate your current agreements and obligations so that you do have time? Is this project more important or valuable to you and others than the current agreements you have? What's the next action that you need to take to find the resources you need? Do you need to post an ad to hire someone?
I'm guessing that time and resources may not be your primary problem. I think that it might be a lack of clarity about your outcome...or perhaps your outcome is just too big to be managed as a project. I'm guessing that it's the former and not the latter.
If you lack any clarity at all on the outcome that you've committed to about these projects then you won't be clear on how to proceed. At that point you have unprocessed "stuff" banging around in your head. Some part of you is going to feel like you should be handling this "stuff" every hour, minute or second unless you are sufficiently distracted by fires and crises (that you may or may not have created). This is what D.A. refers to as "getting caught in the busy trap". While you're trying to distract yourself from that voice in your head that grows louder and louder your energy, inspiration and enthusiasm are being drained more and more because of the guilt created by an unfulfilled commitment that you implicitly made with yourself.
You have three options to get this monkey off of your back:
1. Don't make the agreement
2. Keep the agreement
3. Renegotiate the agreement
If you are absolutely 100% clear on your desired outcomes and inventory of projects and actions is complete and relevant then it's not difficult to exercise these options. My guess is that you're not able to exercise these options because you're not absolutely clear on your outcome or you still have unfinished thinking. It actually can be a project to clarify an outcome regarding some "thing". These projects start with terms like "Clarify", "Look into" or "R&D".
Once you are clear on your desired outcomes then renegotiating other agreements so that you do have time to devote to the pursuit of a project is possible. If you're being honest with yourself and truly do not have time then you'll have to renegotiate that agreement you made to a later date when you will have time...or renegotiate your current agreements if it's important enough for you to tackle it now. You may have to relegate it to Someday/Maybe and learn to feel good about not doing it. As long as you review it regularly and consciously decide not to do it now you shouldn't have guilt about it.