Okay, apologies for the delay in my reply. I work a lot and don't have a ton of downtime.
I finally spoke to Frank at Firm Feel yesterday and he confirmed everything you said. I was having some doubts but you were correct on every count so thank you for your help.
I know that I can always sell what I can't use so I won't be losing too much of my investment. That all said, I see two choices:
--In order to use the Firm Feel fast ratio pitman and idler arms, I have to use the '73+ style center link, but I'd have to purchase it ($350 plus shipping). If I go that route, the 16:1 steering box ratio is out because the car will be terrible to drive at low speeds.
--The rebuild kit I have is the PST polygraphite kit and if I go with the included pitman and idler arms, I can use the stock '65 V8 centerlink that I already have. If I go this route, I can go with the 16:1 steering ratio.
In either case, though, I'm probably going with the 20:1 steering box ratio just for driveability.
I've already gotten the pitman powder coated so I can't return it.
I honestly don't know the tire size off the top of my head, as they're buried in a corner of the garage. I'll post that when I'm able to get to them again.