I just got this guitar for basically free and this thing is nasty and in awful shape, but (especially after it was cleaned up by me) it is a sweet looking guitar that I think can be made playable at best, and a good looking one to display at worst. The problem there is no ID marks anywhere on it and I have taken apart most of the guitar (pickups, controls, neck) to clean it. No ID marks. It seems like a MIJ guitar, but not sure!

Thanks a lot!

That appears to be a Teisco hollow body bass guitar. It looks similar to the guitar model here:

Teiscos were cheap imports back in the 1960s and 70s. Chances were, if you purchased an electric guitar or bass from Sears, it was a Teisco.
It is most likely MIJ, that's a pre-lawsuit headstock. If it's not a Teisco (which it probably is), it could be an old Ibanez or one of the brands that Montgomery Ward imported.
Composite Aficionado

Spector and Markbass
Lovely looking thing whatever it is! Reminds me of the Yamaha that Josh Homme used on the first Queens of the Stone Age album.
I was about to say bass with a trem?!?! but that is not a bass in the second picture. :/
Definitely looks like it came out of the Teisco factory (could have gone under 100 different names) but the control cavity is a bit of a giveaway (I don't think the lawsuit era Ibanez had ones that looked like that, although I could be wrong).
Congratulations, looks like a cool bass. If you ever want to sell it, they've seen a bit of a resurgence lately with the hipsters, but I think that peaked a year or two ago.