to be honest i'd say dont worry to much about engine spec or head gaskets etc, yes they are very important but the biggest prob with saffs is the dreaded rust, after all a blown engine can be fixed without to much bother but a rotten shell means the end, so just pay extra attention to rear chassis legs, sills(inner and outer), inner wings, rear strut mounts and spring plates and the strut tops in the bay, trust me these points are far more important to a good saff than a smokey turbo etc