It seems like it would just be plug-n-play for connections. The odometer should be stored in the computer and not the gauge. I would call Roush tech service, should be an easy answer for them.
chevy runs deep, Don't step in chevy!
289 - Holley 4150 570cfm; Performer intake; mild cam; MSD HEI; 302 heads; Roller Tips; Hedman Tri-Y headers; H-pipe w/Flowmaster 40's; 9 in posi 3.50; 205/50-17F; 225/50-17R.