Manual or automatic?

if you are going drag racing id say you will get easier consistency and have fun with an auto of some kind

if you intend it to be a multi use vehicle the manual does it, you can chase BMWs and Audis on the freeway, surprise a range of modern stuff away from the lights , light up the tyres as you leave coffee and cars.... drift it in the wet and hammer it along country roads.
i have a 4 speed keeps me happy
I do drag race it in an amateur way but really unless you have a lot of 4 speeds you are not gonna have the luxury of pinging the clutch time after time.... you will break something.
which is why i drive to the track run street tyres and just check to see if i'm going faster than last year... i drive in, I empty the car, do an afternoon of passes and get on the beer.

i don't have the time the money or the spare transmissions and clutches to be a consistent manual trans drag racer.. 904 line lock and slicks well it could be different

basically your intended use/application is worth thinking about.
if you drive A to B 90% of the time, when A and B are not 1/4 of a mile apart 4 speed is great. 3.23:1 3.5:1 3.7:1 in the back yeah... it goes and you are not doing ridiculous rpm at 70 mph, go with the softest lightest clutch you can get away with.... test stamp the peddle in 3rd at 40 no slip...all good. clutch plate is cheap transmission rebuild is not

Dave
I don't plan on drag racing. I know the relatively stock 318 wouldn't pull it out of 13 or 14 second passes without a 200 shot of NOS.
But yeah, I want the car to usable for regular driving and occasional messing around. Like accelerating onto the highway, or from red to light. There's been a couple times I've been fooling around and had other cars get in on it. It's all for fun, I'm not looking to race and I stop around 90 MPH.
I've read about guys making the Magnums work in front of 4 speeds. Jamie on Dead Dodge Garage on YouTube clearanced the back side of a 130 tooth flywheel to clear a Magnum flex plate. It worked for him, but I would be worried about affecting the balance of the flywheel.