As always, I'll preface this with the disclaimer that I have but a fraction of time behind bars that most others here have, however...
If you're going to do this I would pick a realistic ENDING goal. Work the progression backwards from there, and use that to choose your starting work set weights. It will mean a deload, but progression in a program is the name of the game right? We physically/mentally need to see the increases as we work, otherwise we're just in maintenance or stalled. I just started a new program and deloaded quite a ways just based on where I wanted to finish the program, not my current 5RM. Had I started at my current max, I would probably be quitting next week from low morale and missed lifts. Looking forward to seeing what you decide, and the results!
My Training Log
Personal tips that I've learned along my still short journey:
Leave your ego at the door.
Prepare. Showing up dehydrated, hungry, and tired will guarantee failure.
Be ready to fight for that grinder of a PR.
Listen and learn. Absorb everything you can, and assimilate that knowledge.
Top Gym lifts: