Did the 3.8 to LS1 swap and having a couple issues w/Gauges

[impaladave1966]

Pulled my 3.8 v6 out of my 2000 firebird and swaped in a LS1 from a Camaro SS 1998. Pulled motor, trany, entire K-member, drive shaft, rear end and all wires, fuse boxes and harnesses. Got everything back together and she fired up on the first turn of the key. Only ran on 4 cylinders as the right side wasn't getting any voltage. Ran a new wire from the fuse box over to the coil pak on right side and all 8 cylinder were a go. Forgot to pick up the old camaro gauge cluster so I purchased a used 5.7L from a 2001 transam. Car runs nice but I have no Speedometer, no Tach, no fuel, no temp. Went to get the echeck done to see what codes I had going on and there was no communications to the OBD 2. They did the old fashion sensor in the exhaust and the car passed. That was great but still done have any gauges used my Garmin to check my speed. Any thoughts on what I might look for as I am headed to the 2000 v6 pinouts versus the 1998 v8 pinouts to see where my trouble might ly. Any help would be appreciated. Dave

[Knight]

Did you transfer the BCM from the 98 as well?

[TLS_Addict]

98 is different than 99 & up, correct?

[Thackdaddy43]

I did the exact same swap and i ran into that problem to. Since you bought a 98 LS1 all the wiring is different so you have to change out the dash harness to fix the problem.