No resinance in cab when windows up or down, my resinator has 3'' on the front and 4''out the back so I installed it direcly to the down pipe next to transmission about 4'' from floorboard on about 22* down and I put a 4x4x4 wye on that 2 pieces of s/s flex and up both sides with 4'' cooling towers,powder coated with s/s perforated heat shields tooooo cool, i'm trying to get some pics online soon,the sound is awesome you can hear turbo spool up and down, no drown no where just all music. I gotta say the stock resinator is all you need, the muffler is not oh by the way I have the 98 1/2 24 valve and as far as I know the 99 has the same exhaust at least for calif. good luck with your exhaust mods,I know I really enjoyed doing mine and it wasn't to hard either Joe Moglia