Hey yall, this is my first post so i hope its not too newbish. anyway i've got an old 12 speed Cerria road bike from the 70's. I'm a college kid so thats all I can really afford. Anyway i've got 7 speed stem shifters on it right now where i've tensioned out the 7th gear. I've got a Shimano 105 RD1050 on the back and a a Shimano FD1050 on the front. i've got several questions.
1. Is the front derailleur index compatible, thats the first major question because I'm running friction on the front mech and i cant find any info on if it will index.
2. I'm thinking of putting a 7 speed freewheel on the back and i know that most that are produced now have a "MEGA Gear". What is the normal spread of teeth for a 7 speed freewheel of that era? or would it be better to just run my 6 gear and tension out the 7th gear again.
3. Finally what would be the best set up, I could buy a set of 2x7 Shimano tourny sti's from amazon for about 80 bucks or should i wait for a better deal on ebay?

Thanks in advance!