Aye Steve,
Cotton buds, brake cleaner and ACF50 applied lightly by cotton bud or spray afore assembly.
If the corrossion is obstinate and you can get the terminals out of the block connector, then the fibreglass fibre abrasive pens do a grand job of removing corrossion with little or no dimensional change. Ebay Lot No. 141114142087. No connection with seller!
A small 'pointy' scalpel blade (Swann Morton No.11 Non-sterile blades on specific handle) can also be useful. Ebay Lot No. 321005245283. No connection with seller!
If things are really bad and there is sufficient length in the loom, lop the block connector off the loom, replace with new connector, soldering the wires to the connectors and applying ACF50 to all before assembly.
My regards, Bill