The bellhousings and statrer etc were the same for the 327 and the 302.
The 350 used a bigger bellhousing "621" and a bigger flywheel @ 14" and a bigger clutch @ 11", a different starter, and a different starter brace.
The only difference between High Torque and regular is the length of the starter body/armature assy. You can interchange the long one for the short one and keep the nose cone etc. It only takes a minute to change once you have done it a few times.