What chassis mods will I need on 440 conversion

Considering dropping in my 440 ( approx 500 h/p ) replacing my above mild 360 into a 68 f.b.
I am thinking shoemaker mounts.
Idealy it would see 80 street /20 strip. I know I will be facing different characteristic manners from the B.B compared to my 360 as I love how the package currently is with steering ( pwr steering) and handling. I feel the 440will have more dip at the front , is this true? ( still running cast heads and don't want to spend on allu heads if I don't need too) sort of doing this on a budget, thus why dropping in the worked 440 opposed to throwing $$$$ on the 360.

As the car is very clean I want to prevent any twisting or putting stress on body / chassis.

To help maintain the integrity of the chassis ( without chopping into anything ) what are my options?
Will chassis connectors help ? How can I improve rear end suspension. I may get itchy and use my t/brake built trans in here too but no massive slicks or tubs planed. Biggest slick it will see is whatever will fit under the rear.
Currently has a 8 3/4 ( with 742 pinnion /crown )

I am open to adding components in keeping the car held together but not real keen on chopping into anything as yet.
Thanks for your input