Lincs to the Past is supposed to be in the process of converting from the now-defunct Flash Player to something more modern. I don't know when that will be done though.
GENUKI has some info about Lincolnshire wills but there doesn't seem to be an online index post-1659 unless the GENUKI page is out of date:
https://www.genuki.org.uk/big/eng/LIN/probate