Tips n tricks for exhaust install

Hi all, not looking forward to this as I'll be doing this on my back, so looking for any advice you can offer.
I bought the Summit 2.5" kit(Heart Throb)
https://www.summitracing.com/parts/sum-680144.
As well as TTI 340 headpipes.
In our 67 cuda FB, console shift 340/904, 8 3/4 factory 340 hipo manifolds 2863549, 2863553.
Also using a right angle oil filter adapter.
Pretty sure that's it for required specs??
I made a lot of cribbing to raise car up, but not sure if I should use axle stands on frame, or on the diff?
Use cribbing with axle stands under diff for safety? This puts diff at ride height so over axle pipe doesnt(hopefully) get squished.
Cribbing under front tires. I'm assuming keep car as level as possible?
Exhaust should be level?
Going to buy some band clamps. Do I get 2.5", or should I buy a "stepped" version?
MOST but not all suggest starting at rear and working forward. I'm thinking ill install the TTI headpipes and then tailpipes?
I've checked Boobtube and there are some videos, but mainly regards to headers and bbodies. One from justmoparjoe was pretty good with what to watch for, altho it's in a b body. I've linked it below. I also left previous hangers installed for reference.
Thanks all.