On the valve train deal I wouldn't normally recommend this but it's been done with good results for years in a truck pulling engine I put together, rules mandated stock appearing valvetrain. It's just got a set of pump builders hd shafts, stock aluminum stands, stock bolts, and new stock adjustable rockers from Napa. It's been to 6500-7000 rpm for 15 sometimes 20 seconds at a time. Also has some drag strip passes/street miles on it. Anyway, good luck with what ever direction you decide to go. You should have a little more torque than my build did, hp would be a question mark, possibly a little more also. BTW my heads had 2.03/1.56 stock OEM valves. By the math on paper using my build as the reference point with hp per cube 396 versus 416 would get you 474hp/470tq, with adding the 428 crank. Would be fun to dyno and compare. Have fun with it.