Originally Posted by cfonnes
I just hooked up a hot tub extension where I had the same problem, no breaker room.
I pulled the front panel (around the breakers) off. I was able to hook the wires to the backplane underneath the lowest breaker.
Be sure to run the correct size wire for the breaker that you are going to use. A spa breaker is 50A GFCI and requires 6 AWG wire.
Not to be a downer or anything, but this is a VERY bad idea. Not only are you overloading your breaker panel but you are also risking your life and property
If there is a fault in your line to your spa panel you have NO protection what so ever and the panel will feed the fault endlessly
and if your house burns down the insurance company WILL NOT pay the claim