I'm closing in on the time to make my car run.

I finished up the Cervini's Stalker kit, subframe connectors will be installed soon, and Koni's (yellows) should be on within a month. Just a few more suspension components and then I'll be going after the engine and transmission.
Here's the goal:
12 second Daily Driver! Honestly low 13's would be fine, but I'd love to see 12s. I want to design a plan so that every dollar I spend will go towards my goal. I know I'll have to get a roll cage, but I figure I should get it out of the 15's before I get one.
Figure I'd start with a block. Which one should I get, 302 or 351? Only concern I have is having to replace my hood, I really like it.

I have a friend with a old Boss 302 that I can probally get for a good price, but besides it having a four bolt main I don't know much about these blocks, will it work for me?
I do plan on building an entirely new drivetrain but, if the stock 8.8 rear will support the final results should I consider getting 3.73's now? I imagine 4.10's, which would be ideal now, would be a bit much with a stronger engine.
I know this is going to take awhile, but someday I will accomplish it. Then when I'm finished and I have an article on pg 52 of MM&FF, I'll be proud to say, "I couldn't have done it without all the great advise from the members of MustangWorks.com"!
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'95 GT Convertable