JD Recipe but with questions

[NMStill]

I found this recipe online but am confused about how to implement it. I am trying to convert it to 5 gallon mash but don't know how to convert the percentages into pounds. I also don't know how much yeast to use. I was planning on using just one 0.176oz (5 grams) package of Red Star Champagne yeast. Is one package enough? I will be putting it into a charred oak barrel to age. I'm sure someone has already tried this....but I can't find anything on it when I do a search.

Thanks for the help.

JD's Black Label Recipe
It consists of 80% corn, 12% rye, 8% malt (a high enzyme 6-row variety will be needed). Steep your ingredients in 140 to 150 degree water for about 1 to 1 1/2 hours. Wait until it has cooled to 68 degrees before adding your yeast. After fermentation, it is distilled once in a pot still with a thumper, then filtered through a 10 foot layer of maple charcoal (this takes about 4 days). It then is placed in new, charred American oak barrels where it ages for 5 years, 6 months before it is bottled. But instead of aging in oak barrels, you can fish out a piece of half burned white oak from the fire place, crush it up and place this in the container with your product. Shake it up once a day for about 3 months and then filter it through a coffee filter for a beautiful amber color. Cut it back to 80 or 90 proof for a smooth taste.

The premium brand called Gentlemen J is aged in the same way, with the same grain bill, but it is filtered through maple charcoal again after aging.

Sweetened with a dash of REAL maple syrup (the kind that has a slight smokey flavor)- this will taste JUST like the store bought spirit- but will be a LOT smoother. The spirit should be aged at less than 65%abv, to prevent vanillins from clouding up the smokey sweetness from the maple syrup.