How much retard, iron heads

How much retard are you guys with iron heads using with 200-250 shot, know it comes down to the complete set up, I just looking at an idea of where things will be at once i get the tune right, how much timing set in distributor and take the rest out with the msd box.... I have a induction Solutions system working with with steve on it was just curious what I'd be looking at and if I could possibly leave the distributor alone and be able to take enough timing out with just the box with iron heads, .....I'm swapping to methanol before I start spraying it and will be using race fuel as an enrichment.

What is your compression ratio? Generally, a common rule of thumb is to pull 2 degrees of timing for every 50 horsepower increase.
That is a conservative or 'safe' timing situation. But you mention running on methanol, which is a cooler burning fuel than gasoline, so you may get by with 1 degree for every 50 horses. You will want to know what the octane rating for the methanol fuel is before you "hit" it with everything you have!!
It is wise to start small....a lesser NOS hit, and work your way up to the bigger hit.

13:1 is what the compression is, going to start with a 100 and learn to read the plugs and work my way to the 250 hit

If you have not done so already, get yourself a air/fuel ratio meter that can read Methanol fuel exhaust, and it will help you with the tune up, big time!