96 Gt Full Build-up Questions

Hello to all you experts in drivetrains and axles i need some advice on a build for 96 mustang gt convertible. here's the quick backstory: car is a weekend/fair day driver, holds sentimental value so we will have it forever, and has about 154xxx in mileage. i know it will not ever be the lightest or fastest car out there but we want to put some power to the ground and have some fun with the car. started project to replace coolant system and found that the radiator support was damaged by someone and damaged the radiator, ac condensor, and brake lines. in the process of fixing this i am also going to replace the clutch and flywheel and change rear gears. i'm not very knowledgeable on what is the best suggestion/needed to do this project the right way so i'm gonna ask a few noob questions and list where i'm at in the project. I have the exedy mach 400 clutch kit and exedy flywheel that need to go in and i would like to change the rear end while were in there (cause why not lol). this is where i get lost on what to get. i'm looking for advice on 3.73 gears, 8.8 rear end questions, 31 spline axles, aluminum driveshaft, new posi-rear differential, k-member, and what i need to get and why it's the best/beneficial vs the cost of the upgrade. ive looked at the Yukon 8.8 rear differential with 31 spline lug axles, does this fit in what i have now? any advice or input that i could get would be helpful. i'm ready to buy what i need and get to tearing this car apart i just need some pro direction from you guys!!! thanks for any help i really appreciate it.

Well to be honest I do plan on making performance upgrades in the future but there are only so many projects I can do/afford at once lol. I may have over researched the rear end upgrades and of course wanted to get the best out of this project and hopefully never have to touch it again. I appreciate the input on the best direction to go with this. so ive got the 3.73 yukon gear kit on the way because I knew that was going to be done regardless. Are you saying that it's not going to be worth it to upgrade to 31 spline axles and the trak loc differential with a slightly tuned engine? We're talking $450 for the yukon kit with axles. If thats the case does the aluminum driveshaft make that big of an improvement with the lighter weight flywheel and 3.73 gears going in? And what type of control arms would you suggest?