Is there a mega thread of election fraud evidence or some website with a compilation

hereistheevidence.com

Are you being funny or are you just that blind?

The site linked by tenderfoot tigah, hereistheevidence.com, is the most comprehensive site I know of with hundreds of entries. It may take a little more time to go through this and click on the source material, which is sometimes videos to understand the basis of the claims, but if you already have a good handle on your arguments and just want to show proof some things have been alleged in the heat of the moment, then this is your best bet.

But it may be worthwhile to check out Sharyl Attkinsson's site as well:

List of significant claims

I believe Sharayl is widely considered a good, legitimate journalist (I think she may still be affiliated with CBS), which can be helpful in citing her work (as opposed to if this were hosted by someone like Alex Jones, which would shut some people off before you start). It is not nearly as complete a list as the other site (hereistheevidence) and I don't believe it's been updated since a month or so after the election (December), but I think it has some use as it focuses on some of the more glaring potential abnormalities / potential fraud and often gives a decent summary of the issue without having to dig into the source material and potentially have to watch long videos to understand the basis of the claim.

And it will help your argument just to know that there's so many potential instances of fraud that more than one person / site has attempted to compile them.