I'm pretty sure that to fit a 7k in place where any other k-series motor once was, you HAVE TO modify the sump (cut and weld). Dad and i cut the 7K sump and then welded it back together. There are some other mods we did as well but i can't remember, so i will have to get back to you on that one.
By the way, my car is a ke30 with a ke55 5 speed.
Matt