I used the Schumacher conversion mounts A73B8 to put the engine in. They come with instructions on modifying the driver's motor mount tower to get it to fit properly. It was pretty straight forward and once I corrected for my own stupidity it slid right in. The K on my 87 required some additional clearance for the oil pump and filter to clear. Be sure to do some fitment tests with the oil pump AND filter on. An additional benefit of using these mounts is that they position the motor correctly to reuse the same transmission mount.
The seam where the firewall meets the floor pan got in the way of accessing the bell housing bolts. Just had to put a couple slits in it then pound it flush with the firewall. This allowed enough room to get a 3/8" extension with a universal socket to get the bolts in.
Exhaust manifolds do in fact fit. I only used them for a couple weeks though as the plan was to swap to headers. I could never find a set that would fit the way I wanted with 3" collectors, so I ended up having a set of mid length headers with 1 7/8" primaries made out of stainless. Worked out better this way as they can be removed with the motor in the car and allow plenty of room to work.
The K frame needed some additional clearance to get the oil pan to fit, but I'm using the Milodon Road Race pan. Looked like a factory style pan would fit without any modification.
I was already running electric fans prior to the swap. A factory clutch fan would definitely not fit.
I can post more photos if you guys want. Cheers!