Okay, I'm still working on this, but I have gotten much closer. That batch I mentioned above, it was fine if you want to try it. Sorry I never came back with feedback, but it wasn't close enough to Henry's. I now have temperature control, and I've begun a different approach.
Although our German/American brewing forefathers used rice, corn, and six-row when they attempted to make something similar to the Czech Pilsner, I have come much closer just using German-based malts, and no adjuncts. Here's my latest attempt that tastes pretty darn close:
5 gallon batch, all grain, BIAB
6 lbs of German Vienna malt
1 lb of German Munich malt
Mash @ 145° F for 75 minutes with:
Remove grains, sparge bag, bring to a boil
1oz Centennial hops
Boil for 35 minutes
Chill to 65° F
OG should be in the ballpark of 1.044
1 pack of Fermentis Saflager S-23 yeast
Ferment in ambient temp of 55° F
On day four, ramp beer temp to 68° F, and leave it there for three days
Let fall back to ambient temp of mid 50s
(I forgot to check FG, but the calculator said to expect 1.010)
Condition for 10 days, then keg
It might not pass a triangle test, but maybe. I'm only on day two in the keg, so it's not quite fully carbonated. As a fan of Henry's, I can definitely say this is very drinkable, and if you handed it to someone, saying it
was a Henry's, they might not question it. Now that I've gotten this close, I might try to start adding rice back into the recipe. I'm new to this cloning business, and Henry's is the first beer I've ever repeatedly attempted to clone from my own guesswork. I don't know if you (OP) still read these posts, but I can't be the only person that cares about this, so I feel compelled to keep sharing my progress. Hopefully someone out there appreciates it.