Wouldn't a 1998 have a 6.5L and either a 4l80E or 4l60E? Seeing as a 98 would be 'fly by wire', I would say have the ECM flashed or reprogrammed.
2004 Chevy K3500 CCLB DRW Duramax. Stock.
1992 Sea Ray 300DA. 30 plus foot Express Cruiser on a trailer. 13,500# boat and trailer and 69' of combined length rolling. Over length/width permitted load.
SOLD-95 GMC K2500 SLE 6.5L TD, Relocated PMD to bumper #9 res., Custom Lowes special induction tube, Triple gauges on the pillar EGT, Trans, Boost, High Idle Mod, TCC-Lock up Mod, Custom Back up camera, DIY Manual Wastegate Controller, 4" from down tube to 5" stacks, Vac Pump Removed,2007 wheels, WMI by Cooling Mist 8gph @3psi 11gph on demand