I understand what your saying. You have to also consider where the motor gets placed if your getting that picky.
even k20:
The H’s & K’s lean back tward the firewall and the B’s sit forward. I’d have to see swapped cars on scales to really fortify an argument though. Even then, like Jlude said the H is making more power across the board. Pull the a/c compressor and put the battery in the truck and you’ve more than compinsated for the H’s weight.
Getting the engine in the car is relativly the same as a B, depending on which mount kit you choose. Some bolt in using the factory mounting positions, but HASport for example uses the front pass. torque mount for the trans mount, so you have to cut the frame rail trans mount off. If you do an EK, you dont even have to do that.
Wiring is the same, you add your vtec wires and any additional wires depending on what ECU u want to use.
Shifter would be next. U have to cut the floor opening to sink the prelude/accord shifter into the tunnel. Make a tin box or whatever and seal it up. Run the cables to the trans and your done.
Axles are fairly straight forward. If you have no intermediate shaft, you can buy an accord one and use all accord axles. If you have a prelude, you can use a prelude drivers and an accord pass. I’ve used all sorts of axle combinations depending on the chassis, the mount kit, etc.
Thats about all of the major stuff. Its definitly more work than a B, but all in all if your capable of swapping a B, you can certainly swap an H.