Dash one Fuse is fine mated with older wings, but...
I started my RV8 in 2005 and was one of the first to receive the Dash One Fuselage. They re-sent a completely new center section. This normally comes with the wings, as they are match drilled as a mated pair. When they sent the new center section, they said that the tooling was accurate enough that the fact that they were not match drilled was irrelevant.
I mated my wings to the fuselage about two weeks ago without a single hitch. I used "pins" that I made from hardware store bolts and they went in fairly easily. So, don't be concerned that the dash one fuselage includes a new center section.
Do not use the one that is with the original wing kit, it will not work with the dash one fuselage.
I echo the other responses, call Van's. At a minimum, get a new set of drawings and instructions, there were a few things omitted from my wing kit drawings (and instructions) that caused some serious head scratching. Vans sent me a couple of revised drawings recently that really helped.