First, there are more threads about this on this forum than you can count. So do a search for more info.
I really can't tell you on the L-82 hood. What I can tell you is my experience with my '72 L-48 hood.
First off, without a higher cowl hood you cant fit the Performer RPM. I put the Performer on mine with the stock Q-jet. It all fit, but I had to pull the sealing ring. The hood would shut, but I was afraid any torque would crack the hood. With that ring off, I measured (using clay-do) about 1 inch of clearance with using a 3 1/2 inch K&N element. Now, I put an Edelbrock Perfromer Carb on her for a while and the stock air cleaner would not fit, due to the drop base and how it conflicted with castings on the Edelbrock carb. So, I tried a $250 Holley Hi-Tech low profile air cleaner. You know, that really cool looking deal they have that looks like dual side draft carbs. Would not work! Even with the drastic drop on both sides it just hit where the sides of the cowl rise in the hood drop down. SO, I used a Edelbrock Pro-Flow for a while (That little triangle foam element jobbie). That worked till I figured out that I was starving the engine with the Edelbrock carb (or it was shot from sitting unused for too long). SO, back to the Q-jet. For some reason, I had a period where she was backfiring through the carb when cold. A couple of those, accompied with flames and that element was toast (literaly)! Back to the stock setup and everything fits.
I think I am done until I make the swap to EFI! Good Luck.