No, not by a log shot . The thing about twin dcoe is that you get independent throttles to each cylinder so you can run a big cam with overlap (long duration) without getting revertion problems. Your setup will be more of a 3k-b thing. One carb feeding cyl.1+2 and other one feeding 3+4 isnt ideal either.
A crossover manifold feeding 1+4 and 2+3 would be better but don't see how on a K.
If you want twin down draught carbs with similar potential to dcoe Id look for idf style carbs. Have seen maifolds for them but rare. Would be fairly tall as well... na, stick to the single downdraught unless youre chasing big hp.
Just my 2c and I'm no expert.
By the way, what else have you done to the 5k ?