67-72 Radiator supports (n00b alert)

[ugotd8]

Hi guys, I'm a little confused. I just bought my first truck, a '72 (http://67-72chevytrucks.com/vboard/s...d.php?t=206571) and I'm starting the resto-rod conversion. I've collected a '68 hood and two '67 fenders. I have to rip off the old front clip this week, since the motor needs a timing chain. I've done some research here and read that I will need to change my radiator support as well. One thing though, this truck I have has the turn signals attached to the radiator support where they would seem to be on a 67-68. I thought the turn signals were supposed to be in the front bumper and expected a jerrry-rig, but the turn signal housings are mounted in stock holes and there is even a molded opening for the wiring plug. I know this truck has a 69-72 hood and a 71-72 outer grille shell, although the outer grille shell is riveted everywhere (did Chevy do that?). So, I have some questions:

1. How can I tell 67-68 and 69-72 radiator supports apart?

2. I am commited to going to the 67-68 front sheetmetal, do I absolutely have to change the radiator support?

3. Can I use my inner fender wells on the 67-68 fenders?

4. How can I tell 67-68 fenders apart from 69-72 fenders off the truck?

Thanks in advance.