HELP!! I have a 79 jim and the 4WD does not work right. I get out lock my hubs, I get back in put it in nuetral, I put the selector up in 4WD LO, the 4WD light comes on my instrument cluster, I put it in drive and the light goes out, wham no 4WD (same with 4WD HI)...If I put continued pressure on the floor 4WD selector the light will stay on and stay in 4WD... this is not acceptable operation...how can I fix this ???