Need your guys input

First off I would like to introduce myself as im new to the forums. My name is Kevin and im from Massachusetts. I have always dreamed of owning a E39 M5 and I finally have come across one im in love with but the deal would include me trading my 2008 Jeep SRT8 for it. My Jeep is FULLY loaded with every single possible dealer option you could add and has 62k miles. The guy who wants to trade me has a 2000 M5 with halo headlight upgrade. Its carbon black with clack leather and only has 35k original miles and is in immaculate shape. How much cash should I ask on top of his M5 so the deal is some what in my favor. Both vehicles are in mint condition btw. I just want to get more input on this before i finalize a deal.

Hopefully ill be more active here if a deal is made.

Thanks!