These days, I'd probably go for a real LCR meter, but not that long ago I wanted to measure a few largish electros and had nothing to measure with, so I made Fr Tom McGahees PIC capacitance meter. I cannot attach the original project as this forum will not accept .rar files ( will accept zips tho)
The PIC he used is now obsolete, so I replaced it with a 16F88, I'll attach the general description pdf, if you want more -->> google it