Another thought at getting that fan clutch loose..do you have a 3 ' screwdriver and a 16oz hammer ? I call it a prybar, try hitting the edge (corner) of the flat ..remember engine rotation direction.I think they will tighten with rotation. I've used JB weld on the pitted aluminum, then backed that up with a good silicon sealant between the cover and block.Carefull with those corroded looking case bolts, that job goes downhill fast when they break..some careful application of heat may help.Anti-seize helps to keep that action from re-occuring,..if you work like me,you will take your time,take everything apart real slow and organized..then if it comes apart real nice, no extra runs to the parts supply needed,...hammer it back together over a few frosties!

Your such a nice son-in-law.. LoL! Good Luck!