1991 2.8d Ln106 hilux problems

Hey i'm not sure if this is the right place to post this but i am wondering if anyone could help me out with a problem i am having with my 4wd
its been sitting for almost three years as i have been away over seas. i come home i go to start it and it just clicks like it's a bad starter/battery
i have replaced both and still it' just clicks it's like it's losing power volts from the battery to the starter motor can anyone give me any advice on how i can fix this problem
i have cleaned wires. battery leads earths removed all rust. with no luck