Regarding the heater core tubes sticking straight out -- I have capped mine for the near-term, but eventually plan to swap the plastic unit currently in place to a brass replacement unit. It may take some scrounging to find one, but I have seen them in the junkyard.

The benefit to the brass boxes is that I can cut and braze 90-degree fittings onto the box to tuck the hoses right up against the firewall. Getting the tubes through the firewall may be a bugger, but I think it is possible, with the right alignment.

I need this space since I kept the stock Ford thermactor-injection crossover tube on the back of my 302.

Randii