450 Engine Swap

[Leewolf]

I just completed swapping out my 450 SLC engine for a 450 SEL engine. There are two problems that hve come up and I'm looking for help or ideas on solutions.
1. Hot start problem: I have a real problem starting when the engine in warm?hot. This problem has occured with both engines. I have changed out the coil and coil wire and the problem remains. Incendental to this problem this engine heats to about 110 deg C (230 deg F), it takes about 20 miles to reach this temp and gets there quicker if I'm running over 70MPH. ANY THOUGHTS?
2. Exhaust Manifold Flange (passenger side) touches the frame. The 450 SEL engine bolts up just fine needing only a change of the oil pan and exhaust manifolds from the 450 SLC engine. There is appearently a smal dimensional difference in the 2 engines. Does anyone have any experience with this or suggestions ? ANY THOUGHTS
I removed the CATS and put pipes from the exhaust manifolds to the muffler. I have definatly picked up some horses and the car sounds great.
Looking for thought or help!!