B18C1 vs B18C5 vs LS/GSR

My 99 GSR needs a new motor bad. I have a LS block GSR head that (was) built by a dickhead who royally screwed it up. It leaks oil from where the block comes together with the head and burns a little too. I was wondering do most people have trouble with this type of hybrid or is mine just completly fu**ed up. What do ya'll think???

I think my head is ok, so if you recommed I go back with a LS block and build it again, just right this time, then it would prob be cheaper. This is also going to be a daily driver and N/A car.

Could be a blown head gasket, or improperly installed head, who knows. Open it up and look inside. Check to see if the valves and pistons have been hitting, unusual scoring, and broken stuff in general.