JMO, but you have quite a mismatch. First, with all the induction hardware, why are you going to use a streetmaster? A streetmaster will really wake up an 390, but even if you do the suggested porting, it will poop out around 5000-5500rpm. They are great for velocity but have too small of runners to do any heavy breathing. Use a Edelbrock Victor instead. Already has unmachined bosses. You also have too much induction for a .060^ 390 with a step up from stock cam. You will leave hp at the starting line with that setup on a 390. I would look for a good 428 or a reverse 105 block. Don't get sucked into buying some 'rare' 427 ($$$). New blocks can be had for not much more. Stock rods and crank will work. Ditch the cast pistons. You can find some good used forged if you look around. Headers are a must to match the induction.

Lastly, if you just decide to go with a big S intake and an autolite 4100, pls send me your leftovers.