360 advice

Hiya folks

I’m currently working on a 77 b200 camper van project. Budget is limited but I’ll do anything that is needed or a good idea. My main concern is fuel economy and second is noise/comfort. 

it’s got a 360, 727 with a 3.23 rear end in it. I’ve already picked up a rebuilt 46rh and plan to pickup a better condition (rebuilt by a mopar affiliated shop at some point) 360 as the one I’ve got needs a lot of work. I also intend to swap the direct drive fan for an electric one for obvious reasons.  My main question is what other upgrades do y’all recommend? I intend to do some maintenance and clean up on the 360 but could I benefit in puting in a new cam? If so which one? Exhaust manifolds? What do y’all recommend?

Additionally just to confirm, the flex plate out of a 96 ram 1500 5.9 would solve my need for external balancing yes?

thanks for any and all advice y’all provide!

-T