Max weight for a toad

[morganaire]

Hi guys -

Looking a buying an SP36 in the near future, and am hoping to get some input regarding our toad. I currently have a Lexus GX470 that weighs in a just over 5K pounds and would LOVE to use this as a toad. I know it's heavy, and I know a lighter rig would be better, but I love my Lexus (if you saw her you'd understand), and would love to tow her around without feeling like I was either abusing the 'Bird or dialing my MPG's down to near zero while towing. Any sage advice? Should I sell and get a lighter toad or can a SP handle this old girl?