Seized bolt on top of the transmission

NEED IDEAs

so trying to remove my 6l80e 2wd off a 5.3 and all the other bolts came off no problems but this one nut on the very top stud. I believe I can still get a good grip on it but it is starting to strip. Ive tried heat (cheaply propane, torch), wd-40 and my impact at full power. It is a Nut in a very hard to reach spot and I don’t have much room

HMU with anything kinda stuck and need a ride to work tomorrow

 

I've had this same issue on my 2022 Silverado with the 6.2L and the 6L80E, getting that top nut off can be a real pain, I've found using a small impact wrench and a ratcheting socket can give you a little more control and leverage when it comes to getting it loose.