Exhaust question/opinion

[sleazy rider]

i bought my 91 zr-1 from the original owner in jan 2020. during his ownership of this car he had taken it to lingenfelter for the 475 hp package and then later shipped the engine to him for lingenfelter's 368 cid 530 hp package. now that i own the car, #1299, i procured a set of stainless works 2" headers with 3" collectors thru the zr-1 registry. also included were 3" cats and 3" mid pipes and had everything jet hot coated. i also bought a 3" internal 'x' resonator which leads me to this question. coming out of the resonator should i:
1. finish out with 3" exhaust to the mufflers which are 2 1/2" borlas
2. finish out with necking down from the 3" to 2 1/2" from the resonators to the mufflers
the muffler shop can get either size tubing to do the job but had no input on which size tubing i should go with for an efficient exhaust.
what is your experience or opinion?
thanks