yet another exhaust question

[LowNslow]

hello all ive really enjoyed reading everyones posts on this site but ive got a question that i cant seem to find the answer to....i have a 98 gmc ext cab 2wd with a 350 and i put the ever popular duals on it and i had the convertors taken off due to the fact they were in bad shape and ive ordered the o2 sensor simulators but my question today is i know we have the 1 7/8 inch pipe coming off the manifolds but whats the actual size of the collector on the origional cast iron manifolds? is it 2 inch or 2.25? i have no desire to run headers because i dont want the headache...thankyou guys in advance