408 build in Australia

VF! I have a 410 in my charger. It had the 1 5/8 pacemaker headers on it with twin 2 1/2 inch exhaust. Had edelbrock home ported heads on it with air gap manifold and made 355 rwhp and ran 11.7 qtrs. I changed to the 1 3/4 into 2 inch into 3 inch collectors and 3 inch exhaust and power went up to 392 rwhp.Ran an 11.4 qtr. I then changed to trick flow heads , victor 340 manifold and next size up cam(237, 243 @ 50 with 610 lift) It now makes 425 rwhp but 1 5/8 pacemakers are too small for a stroker so as you can see the latest pacemakers make 37 more rear wheel horsepower with about 45 ft lbs more torque. Those trick flows cost me about $4500 landed but that was @ our dollar at 71c but is a lot better now. I have a set of speedmaster heads that I bought bare for $1000 and sent them to a guy in your state to do a full port job on and he charged me six grand but put 200 thou longer valves in but when I questioned him about the valves he said he always does that. I sent the valves back and eight months later he sent the correct valves. These heads owe me seven grand but I would take about half that if you know any one that wants them. They have 2.08 inlet valves in them and have a full port job and quality parts in them.