New to Mopar

Nice car! I had a 66 Dart same set up 273 235 hp four speed. I put Mopar heavy duty valve springs and moved it up from 5200 rpms to 6000. I ran Cyclone fender exit headers, and I then put in a 4:89 gear and ran M&H ripple wall slicks on the street. Left the light at 6000 rpms and I was gone. Had to sell it to finish school in 1972
Just bought another 66 Dart with a 273, 727 auto tranny 8 3/4 posi rear end. I was wondering where you are finding parts. With the change in intake bolt patterns in 1967 I am having trouble with parts. Where are you finding parts?
Thanks!
Art Clark III