Now that's the part you should clear coat so you can look underneath and drool every time you go out to drive it!
To your previous thought, yeah it would be nice to look at all the nice sheet metal too, but it's the insulation and sound deadening that's going to make you grin every time you drive it more than a mile away from home.
Lizzard skin sound deadening, and because you're at this point, also a layer of the heat-barrier coating on top of it, will make a world of difference.
And don't under-applicate it either. Get all the way up inside the wheel wells, quarter panels, front fender kick panels, and don't hesitate to put it all the way up the firewall and on top of the cowl.
Yes, you will lose that nice smooth painted metal look where all eyes fall when you open the hood. But if this is going to be more than a show car you will appreciate the peace and quiet and moderated temps inside the cabin.
And so will passengers.
It's that big a deal...
Paul