Hi Jake @jakedduck1 -- I take the D3 - 5000 IU capsule twice a day as part of my neuropathy supplements I found in the closed Facebook Group Solutions to Peripheral Neuopathy Pain & Discomfort - https://www.facebook.com/groups/SPNPD/. They also have a website (http://solutions2pnpd.com/). The D3 is at a therapeutic dosage level which helps get the usable form into the body. Best description I've found that supports the higher dosage is here:

Driving up the dose: implications for high-dose vitamin d therapy - NCBI
-- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4824637/

Vitamin D - Doses & Uses
-- https://reference.medscape.com/drug/drisdol-calciferol-vitamind-344417

Dose vitamin D supplementations improve peripheral diabetic neuropathy? A before-after clinical trial.
-- https://www.ncbi.nlm.nih.gov/pubmed/30641826

I get blood labs on a yearly basis as part of my regular checkup.