opinion on this complete exhaust system?

Mike,
you would have to ask someone more knowledgeable than me but i believe the 74/75 are basically the same car so i would think the only difference would be that the 75 has a cat also this would be the first that i heard of stainless exhaust this early on a production car if it did come with stainless.

also hit your custom exhaust shop and ask them how much for an exhaust with the muffler you are looking for just remember not all shops carry all brands of mufflers
and may try to sell you something else and if its not what you want dont buy it as you wont be happy.
personally i have had flowmasters, thrush,cherry bomb,magnaflow,etc,etc,etc over the years and found that i like the sound of the magnaflows the best.