Fuse Panel Block Replacement?

[DJ_Baar]

Recommendations for replacing fuse panel block that goes thru firewall? Windshield gasket leaked and fuses were rusted in place. And hack job on engine side needed work, so thought I could just take apart and repair. WRONG the bolt that goes thru the firewall is either superglued or rusted.

I did try cleaning-up the fuse panel but needed to disconnect the firewall connection for more play with the wiring (and some needed repairs/replacement.

Pictures are of complete fuse panel, inside, and engine compartment block. So much corrosion on connections inside fuse panel, really want to replace as corrosion creates heat with poor connections. (I did do my best to clean - but....)

Appreciate the feedback up front.

R/
DJ