apples vs. oranges
A sniper system utilizes a wide band and therefore is able to learn/deal with afr changes much better than a GM TBI.
You do NOT want EGR active @ idle.
Hookup would be ported vacuum to a CTO to EGR.
A delay valve may be needed as well? To prevent hesitation when opening.
The CTO would prevent EGR until engine is fully warmed up.
It will not be an ideal setup, but I see no harm in experimenting.