Looking for opinions - drop/tires/wheels

[kcjones]

I have a 67 C20 that I want to drop (pictures below), convert to 5 lug, and add power disc front brakes. I'm looking for some opinions here:

I'm thinking 3.5"/5" drop, using rear 295/50/16 on 16x10x5bs, and 255/50/16 on 16x8x4bs on front.

-Will my rear tires stick out beyond the bedside fender lip?
-Will my front tires be "too short" (I don't want anymore than about 1.5" between tire and fender lip).
-In measuring my axle [Eaton HO52] to frame clearance on stock springs, it looks like I only have about 5.5" the HO52 is being replaced by 73-87 12bolt 3.42/Posi- I hope this is spring lag, but is it possible that 3/4 tons are different frame-wise, and I'll need to c-notch to go 5" lower?
-While I have everything out, should I go to a 1 piece driveshaft?
-Can I use a 2" drop spring (to get 4.5" drop in front) without negatively affecting caster too much?

I know it's a lot of questions (sorry), but I also know the collective knowledge on this site is exceptional.

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