5 or 6 speed conversions??

Gear Vendors has a unit but its pricey.

And only .78 reduction. Not really worth it unless you find one cheap/used, IMHO.

The T-5 swap is the best option to me, if you have the ability to fabricate a lower crossmember and don't mind cutting on the floor and upper crossmember. Several tranny/overdrive options, new or used. I've got one of the bellhousings, but haven't gotten around to using it yet.