Replacement Springs and Bars

first of all welcome to FABO.

if you're keeping the /6 for awhile you'll probably be happy with the .92 bars. 1" would be ok too but may be a bit stiff for regular cruising.
on the rear, just stay away from ss springs as they will raise the back of the car. hd springs will provide a good firm ride and keep the heighth stock. i think some vendors can also provide de-arched springs if you want to go lower. i don't know if they are still in stock, but there was quite a buzz awhile back about the good deal that j.c. whitney had on replacement a-body leaf springs. maybe somebody else can chime in on that. good luck!