To perfect, this will be a project that will probably take quite and few years to make and refine. Since the lionhead breed itself is still under works, you should try to find a very exceptional one. Your lop should also be a very nice one. You'll have to cull harshly for results. I would probably breed to DM with a nice dense mane than a single mane. I normally see a bunch of single mane that just have a couple of strands left because they just loose them when they are seniors.
Do research into your breeds first too. I have a bloodline of Mini Lops that I introduced and they lop quick, heads are massive, and they grow like weeds. Westcoast bloodline lops are just better. I couldn't get anywhere near the same results in the same amount of time.