The only way I know to definativly diagnose a cracked block is with dye. Block has to be cleaned and out of vehicle. Then taken to a automotive machine shop. Your symptoms could very easily point to a head gasket. By the looks of your first pick you have a head gasket issue on the lifter side back. Could also be a slipped liner, I dont know if you can diagnose that without pulling the pistons, or when its still assembled. Try and get in contact with PTSchram or DiscoMike.
03 Disco S, 71k. Done- rear dif, front driveshaft, 2" OME lift and shocks, Kumho MT KL71, every stinking gasket on the engine and oil pump, wires, plugs, t-stat. Locking TC.