69 Dart Swinger 340 road race mini tub question

I am currently working on the chassis of my dart and i'm on the fence about installing the mini tub kit I bought. I am installing the inboard leaf spring kit with Hotchkis -1 leaf springs and their HD shackles. I'm planning on running 18x9 or 9.5 wheels all the way around with most likely 275/35-18's as well. I believe they will fit the original rear wheel wells, but i'm wondering if I should just mini tub it now while the car is stripped down. I will probably get some 15x10" wheels with drag radials for the few times I drag race it, but that's about it. So my question, do I mini tub it or just leave the rear wheel wells uncut? (I don't really care about cutting the body to do this, it's a driver not a restoration or show car)