sublettm, you are lucky, to have nursed it back to Houston without engine failure.
The factory Campaign (Wasn't Napolean's wars called that?) will be a God-send. I was lucky to have bought my '87 after the PO went thru that ordeal. He had the local dealership perform the Trapectomy
You should have read up on the subject here, before you put too many miles on the car!
The '87s are a marvelous combination of innovation and automotive engineering.
I just completed a long trip in my W123 turbodiesel wagon, CA to Tyler TX, and wished along the way that I was driving my '87 300D, the extra acceleration and better fuel economy would have been welcome but the old '85 chugged along just fine. OTOH I probably would have been the recipient of a speeding ticket in Texas where I was coming up on a State Trooper at 85 MPH in a 70 MPH zone near Pecos, TX when I spotted a timely off ramp and took it in a seconds notice in a fortunate gap in traffic in the slow lane.
DDH
Oh yes, I always carry a jug of 15W40 DELO in the trunk in case of something like what you went thru (but I use Amsoil synthetic in the 603 engine, it loves the stuff).