Help convince me to go BB in my Duster?

So far I definitely will need disc brakes, a rearend and driveshaft, and was going to do torsion bars regardless. Do I need to modify the K-member?

I had to grind my /6 ears down and drill new holes, no big deal. Total cost with you having a motor, resealing, header, install kit, exhaust, rad around 1500 or close. If you have a 8 1/4 it will hold up to 450hp or so. 7 1/4 take it out.