bell housing install issue

[hoopty5.0]

Im putting a lakewood blow-proof bell housing in my car. Its a large unit and I couldn't get it into position since I have long tubes on my car. Do I have to take the headers out all together or can I just loosen them up?

Thanks,
Collin

 

[Rick 91GT]

Easiest to pull one side off...ive had to slightly grind and clearance the bell to fit certain longtubes...