Some diagrams show both grounds going to the wiring harness and others (like yours) show one going to the chasis. Whats the worse that would happen if you dont have one going to the chasis? Im guessing it would just cause your car to stumble and **** at high rpms.
Also, what gauge wire did you use to connect to the chasis?
'91 240sx hatch- s14 block, s13 head, s14 intake/s13 exhaust cams, Supertech 8.6:1 pistons, eagle H-beam rods, arp hardware, jgs starter kit (T3/T04E 50 trim .63 A/R), tomei 740's, ebay i.c. kit, HKS SSQV, 3" piping tubo back, efi specialists ecu, walbro 255, safc 2, plx m-300, knocklite
'93 240sx coupe(DD)-aem intake!!!