Exhaust Size Recommendation

Hello everyone, first off I'd like to thank all the people here who have given me advice for my projects after all these years. My current build is a 1966 Bronco with a 429/ZF 5-speed. I'm getting custom stainless headers built for it soon and I was wondering about what exhaust pipe diameter I should go with. Then I saw magnaflow has a full bolt in dual 2.5" system with an x-pipe:

http://www.magnaflow.com/products?partNumber=15344&searchTerm=15344#modal-compatiblevehicles

Looks like a beautiful exhaust system. I've had a full kit from them before and I really liked it. My issue is that the pipes may be too small as most people on here run 3" systems. Here's a breakdown of my engine combo:

429cid (0.060 over)
11:1 compression (flat tops with SCJ valve reliefs)
FRPP SCJ heads (Intake valves backcut)
Solid roller with 239.5in/244ex (@0.050) and 626In/654Ex Lift
Performer RPM Air Gap converted to EFI (Ports matched to SCJ height)
And if it matters 3.73 gears with 33" tires

This will primarily be a fun street toy. Will the 2.5" system work or will I be giving up a lot to use it?

That is not to small for a street system when using straight-through mufflers with a 429 size engine.

I agree would be near spot on.

Thanks for the replies. As my transmission and tcase are not stockand also I have to go outside the frame for headers, I will have to toss the 2 pipes forward of the x-pipe. It looks like the system can be modified easy enough to move the xpipe rearward 1 or 2 inches. That's all I'd really need. I might pull the trigger on this system in the coming weeks. At the very least I do have a 3" x-pipe kit on the shelf that I can use, but the idea of a bolt in system is much nicer.

So my previous post was about a starter, this one about exhaust.. Starting to see the light at the end of the tunnel.

Well tdotperformance.ca had a big Magnaflow sale. Then they had 10% off for Black Friday. Then free shipping. So I had to do it. a 2.5" mandrel bent exhaust with an x-pipe for $877cad. If it installs half as easy than my last exhaust I'll be happy.