Axle swap Hidden costs?

[DnvrJay71]

I have a 1971 K5 Blazer It's a 350- 4 in block lift and 33 in tires. It currently has the standard d44- gm corp 12 bolt setup. All I really wanted to do initially was get it re-geared. It's dog slow off the line. Currently running 3.08's with a 4 speed manual tranny. after looking into it, I found local shops are in the neighborhood of 1000-1200 to put 4.10 or 4.56 in.
That started me thinking, should I avoid wasting the money on new gears and just swap out the axles for a 3/4 ton 14 bolt ff and dana 44 8 lug? Or are there going to be a lot of "additional costs" involved?

If I find a pair of 3/4 ton axles what else am I going to have to purchase?
8 lug rims
U-Joints
Spring perches?
brake lines?
new lift?
can I swap any of that stuff over?
What else should I be thinking about...... I'd like to put on 35 in tires and run 4.10 or 4.56

Thanks for your help. I really don't know what I'm doing ;-)