I will suggest to do not do the partial payment.
Because right now maybe they accept without any issue. But after 3-4 years when all the payment will be done, then bank will have something very firm in their hand to raise the discrepancy in the documents.
They will say the payments are still short (though you have already paid as partial payments).
But what if they say oh… xyz person who collected those payments is working in bank no more and neither he updated the system.
Imagine this situation and consider to pay the payments in full.