Intake suggestions

Need some opinions on choices with intake manifold. Not sure I should have posted in this thread or in the fuel section but I looked for other intake questions and most seemed to be posted here.
First let me tell you what my combo is with out the intake. I am building this in a 66 Dart. I have a 408 with 10.5:1 compression. Dish, with a D-shaped cup pistons. My cam is a comp solid roller cam that will be intake and exhaust lift of .575 and duration at .050 262. lobe sep is 110. rockers are harland sharp 1.5. heads are factory J heads with 2.02 / 1.60 valves and some porting. Dont have flow #'s. TTI 1 5/8" to 1 3/4" step headers with 3" collectors and a 3" TTI X pipe. running a melling HV oil pump and 8 qt milidon pan. The trans will be a built 904 with a Dynamics 4000 Stall converter. 8 3/4 rear with 3:91 gears. Hope I didnt miss any important information there.
Originally I bought an old Edlebrock TR5 2x4 intake that had 600 holleys with it. Probably a late 70's intake maybe early 80's at best. It came with linkage and 2 new carb rebuild kits. I already have one carb done and ready. It had been quite some time since this setup had been used but the price was good.
Now here's the reason for questioning myself and it has more then one potential problem if I continue on my original plan of using this.
1st - I plan on drag racing this car 3-4 times year. Im hoping to run mid 11's?
2nd - the 2x4 manifold is very high and i havent been able to set the engine in yet, but I am positive the carbs will be out thru the hood. I purchased an old style pro stock 5" (Unlimited PR-12) hood scoop but im still not sure it will fit under it.
3rd - my intake is going to need some machine shop work, as I inspected the intake closer I found that both the water outlet bolt holes will need helicoils put in them as the threads are gone. Also both, the heater hose pipe and the by pass pipe are that tight that I havent been able to break them loose meaning theres a very good possibiltiy its going to need to be rework at the machine shop. That means throwing more money into this set up. Yes ive tried heating both pipes and soaking with PB Blaster but it continues to just collaspe the pipes instead of breaking loose.
4th - I am sure that a 2x4 set up is going to take more work and adjustments on a regular basis which leads me to my question and reason for this thread.

Should I throw in the towel on this setup and just buy a single carbed intake? Im sure that it would make a simpler set up and Im sure less hassles. It wouldnt have as much of a wow factor but would probably be a lot less head aches.
If so what are your recommended intake and carb combo's? manufactor's? CFM?

How much will a single 4 compared to a 2x4 setup effect my 1/4 mile times? Better or worse?
Damn, I really had my heart set on the 2x4 but Im thinking its more trouble and hassle then its worth. And I have no idea if the carbs have or had any issues in their past life.
Looking forward to your thoughts. In advance I thank you for any information you can help with.
Thanks
Rod