Long-off 340 build

Yeah the trans and cam are the only things I'm unsure of thus far. I considered a 5-spd but I didn't know of any particulars, I've heard of guys using 5-speeds from the 90s dakotas but I also heard those take some modding to fit and have a tendency to break (not like they're being bolted to big blocks or anything). I don't know of any other tranny that'll bolt on.

As far as cams go that thumper seems a bit wild and whacky for my goals (I was looking at roller cams for it and that's the mildest roller jegs had). I want something that will be a fun street machine, but not too much to the point where it only gets 9mpg and I can only afford to drive on the weekends. A light, sporty V8 that I can screw around with when I put the pedal down (not that I'll be breaking speed limits or anything, wink wink) but I can put on OD and be able to drive on the highway without revving out at 5000rpm and burning my mpgs (which is why I was questioning either a 4-spd w/ an OD unit or a 5-spd, cuz it's not like I'm putting big block torque to it).

As far as "expert" help, like I said I know someone who has a bit of history building cars, so he helped me get an idea where to start narrowing down my preferences. I also have my uncle with a bit of experience himself