Stage 2 full length 2 1/8 primaries must be installed in the car before the engine, lifting one side or the other, or from the bottom WILL NOT WORK! Save yourself the time and effort and move forward with that knowledge. We tried every other way possible trust me.
The 2.125 tube are a nightmare for sure....I had no luck setting them in first...wouldn't come up over the deck of the block...but I'm always by myself too....I had to set engine about 8in from the mounts and shift engine over then do the pass side same way all while lowering it down....no dents needed and only few scratches. The way it goes around the control arm mount...it makes it absolutely impossible otherwise....as does it make it impossible to service or change the control arm as the bolt won't clear for removal
Good information back in 86 when I swapped out the factory stage 1 heads for the factory stage 2 heads , I don’t recall having a problem probably that’s because I dropped the headers in while the heads were off there’s Nothing like opening the hood and having the Kustom stage 2 headers staring at you.