will gen 4 camaro seats work in a 70 camaro including the rear seats

 

Probably best for you to measure the bolt pattern on your car, and the 4th gen, then determine if they match. Same for the rear. Measure width, and check the clips that hold it in. The U Pull It yards are a good place to go for taking measurements, and checking fitment.
The front seat mounting can be reworked if it's off. A little cutting and welding will make anything fit. I reworked Durango leather buckets to fit in my '69 Suburban this way. I reworked a folding Taurus SHO leather backseat to fit in my '63 Falcon also, and nothing matched. I cut the hog rings, and pulled back the leather to cut down the framework by 1.5" on each side. Then pulled the leather back over and hog ringed it again.
Put a pair of Mustang II buckets in the front, and had to rework all 4 mounting brackets, but they look great and fit well now.
Anything can fit, if you want to use it, and don't mind some reworking.