Feeling rather stupid again lol, I done what I already worked out when putting the cav pump injector back on, I forgot to take the sproket and fit it to the cav first. the engibe it does work but the cav pump is not connected in order to rotate to pump diesel to engine hence it not starting again, bar that got tub back on the S2a, i have the rear section complete and took all the self tapping bolts out and replaced them with rivets. it looks so better and there flush so getting there slow but sure.