72 suburban exhaust

[gregory whitney]

Can anyone out there tell me if the exhaust manifolds I have from a 67 big block Impala will work on my 72 big block suburban? Also would the stock exhaust have been dual or single? The guy I bought my Burb from has a set of headers on it with an H pipe and flow masters exiting in front of the rear wheels and I can't take the noise. Also, all the heat and the A/C come out from the dash vents. Moving the levers on the control panel does not move the air flow to the defroster vent or the floor. Where shoud I look first to try and fix this? Lastly, the truck came with a set of 22 inch wheels and tires that I would like to sell. Stockers are more my style.