Doug's Headers in 64-66 A-Body

Hello All

Looking to put my 66 Barracuda back on the road after 25 years +. Doug's advertises that their Part Number D450 fits with a 4-speed in the 273-360 configuration. My car is 340, with manual steering. Has anyone used Doug's in the early A-body configuration and was there any or much massaging required to gain clearance? I have not decided if I will stick with the standard throw-out bearing/Z-bar or go with the hydraulic set up. If anyone has worked through a similar project on the early A using Doug's, I would like to hear about the experience. I did review the earlier post related to the Doug's later A body header installation.
Thanks.