Motor Mounts

The 62540s are just replacements for the rubber insulator part. You still need the engine bracket.
The 62520s are for B bodies.
Use these:
'67-72 A-Body V8 K-member to 273/318 or 340/360 – Schumacher Creative Services Inc. - Engine Swaps (engine-swaps.com)
Order the 340/360 style.